feat: command surface and slash completion wiring

Add a renderer regression test for long non-JSON tool output so the CLI's fallback rendering path is covered alongside Read and structured tool payload truncation.

Constraint: This follow-up must commit only renderer-related changes
Rejected: Touch commands crate to fix unrelated slash-command work in progress | outside the requested renderer-only scope
Confidence: high
Scope-risk: narrow
Reversibility: clean
Directive: Keep truncation guarantees covered at the renderer boundary for both structured and raw tool payloads
Tested: cargo fmt --all; cargo test -p rusty-claude-cli tool_rendering_ -- --nocapture; cargo clippy -p rusty-claude-cli --all-targets -- -D warnings
Not-tested: cargo test --workspace and cargo clippy --workspace --all-targets -- -D warnings currently fail in rust/crates/commands/src/lib.rs due pre-existing incomplete agents/skills changes outside this commit

rust/Cargo.lock

@@ -111,6 +111,7 @@ dependencies = [
 name = "commands"
 version = "0.1.0"
 dependencies = [
+ "plugins",
  "runtime",
 ]
 
@@ -825,6 +826,14 @@ dependencies = [
  "time",
 ]
 
+[[package]]
+name = "plugins"
+version = "0.1.0"
+dependencies = [
+ "serde",
+ "serde_json",
+]
+
 [[package]]
 name = "potential_utf"
 version = "0.1.4"
@@ -1092,6 +1101,7 @@ name = "runtime"
 version = "0.1.0"
 dependencies = [
  "glob",
+ "plugins",
  "regex",
  "serde",
  "serde_json",
@@ -1181,6 +1191,7 @@ dependencies = [
  "commands",
  "compat-harness",
  "crossterm",
+ "plugins",
  "pulldown-cmark",
  "runtime",
  "rustyline",
@@ -1546,6 +1557,7 @@ name = "tools"
 version = "0.1.0"
 dependencies = [
  "api",
+ "plugins",
  "reqwest",
  "runtime",
  "serde",

rust/crates/api/src/sse.rs

@@ -216,4 +216,64 @@ mod tests {
             ))
         );
     }
+
+    #[test]
+    fn parses_thinking_content_block_start() {
+        let frame = concat!(
+            "event: content_block_start\n",
+            "data: {\"type\":\"content_block_start\",\"index\":0,\"content_block\":{\"type\":\"thinking\",\"thinking\":\"\",\"signature\":null}}\n\n"
+        );
+
+        let event = parse_frame(frame).expect("frame should parse");
+        assert_eq!(
+            event,
+            Some(StreamEvent::ContentBlockStart(
+                crate::types::ContentBlockStartEvent {
+                    index: 0,
+                    content_block: OutputContentBlock::Thinking {
+                        thinking: String::new(),
+                        signature: None,
+                    },
+                },
+            ))
+        );
+    }
+
+    #[test]
+    fn parses_thinking_related_deltas() {
+        let thinking = concat!(
+            "event: content_block_delta\n",
+            "data: {\"type\":\"content_block_delta\",\"index\":0,\"delta\":{\"type\":\"thinking_delta\",\"thinking\":\"step 1\"}}\n\n"
+        );
+        let signature = concat!(
+            "event: content_block_delta\n",
+            "data: {\"type\":\"content_block_delta\",\"index\":0,\"delta\":{\"type\":\"signature_delta\",\"signature\":\"sig_123\"}}\n\n"
+        );
+
+        let thinking_event = parse_frame(thinking).expect("thinking delta should parse");
+        let signature_event = parse_frame(signature).expect("signature delta should parse");
+
+        assert_eq!(
+            thinking_event,
+            Some(StreamEvent::ContentBlockDelta(
+                crate::types::ContentBlockDeltaEvent {
+                    index: 0,
+                    delta: ContentBlockDelta::ThinkingDelta {
+                        thinking: "step 1".to_string(),
+                    },
+                }
+            ))
+        );
+        assert_eq!(
+            signature_event,
+            Some(StreamEvent::ContentBlockDelta(
+                crate::types::ContentBlockDeltaEvent {
+                    index: 0,
+                    delta: ContentBlockDelta::SignatureDelta {
+                        signature: "sig_123".to_string(),
+                    },
+                }
+            ))
+        );
+    }
 }

rust/crates/api/src/types.rs

@@ -135,6 +135,15 @@ pub enum OutputContentBlock {
         name: String,
         input: Value,
     },
+    Thinking {
+        #[serde(default)]
+        thinking: String,
+        #[serde(default, skip_serializing_if = "Option::is_none")]
+        signature: Option<String>,
+    },
+    RedactedThinking {
+        data: Value,
+    },
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
@@ -190,6 +199,8 @@ pub struct ContentBlockDeltaEvent {
 pub enum ContentBlockDelta {
     TextDelta { text: String },
     InputJsonDelta { partial_json: String },
+    ThinkingDelta { thinking: String },
+    SignatureDelta { signature: String },
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]

rust/crates/api/tests/client_integration.rs

@@ -75,6 +75,48 @@ async fn send_message_posts_json_and_parses_response() {
     assert_eq!(body["tool_choice"]["type"], json!("auto"));
 }
 
+#[tokio::test]
+async fn send_message_parses_response_with_thinking_blocks() {
+    let state = Arc::new(Mutex::new(Vec::<CapturedRequest>::new()));
+    let body = concat!(
+        "{",
+        "\"id\":\"msg_thinking\",",
+        "\"type\":\"message\",",
+        "\"role\":\"assistant\",",
+        "\"content\":[",
+        "{\"type\":\"thinking\",\"thinking\":\"step 1\",\"signature\":\"sig_123\"},",
+        "{\"type\":\"text\",\"text\":\"Final answer\"}",
+        "],",
+        "\"model\":\"claude-3-7-sonnet-latest\",",
+        "\"stop_reason\":\"end_turn\",",
+        "\"stop_sequence\":null,",
+        "\"usage\":{\"input_tokens\":12,\"output_tokens\":4}",
+        "}"
+    );
+    let server = spawn_server(
+        state,
+        vec![http_response("200 OK", "application/json", body)],
+    )
+    .await;
+
+    let client = AnthropicClient::new("test-key").with_base_url(server.base_url());
+    let response = client
+        .send_message(&sample_request(false))
+        .await
+        .expect("request should succeed");
+
+    assert_eq!(response.content.len(), 2);
+    assert!(matches!(
+        &response.content[0],
+        OutputContentBlock::Thinking { thinking, signature }
+            if thinking == "step 1" && signature.as_deref() == Some("sig_123")
+    ));
+    assert!(matches!(
+        &response.content[1],
+        OutputContentBlock::Text { text } if text == "Final answer"
+    ));
+}
+
 #[tokio::test]
 async fn stream_message_parses_sse_events_with_tool_use() {
     let state = Arc::new(Mutex::new(Vec::<CapturedRequest>::new()));
@@ -162,6 +204,85 @@ async fn stream_message_parses_sse_events_with_tool_use() {
     assert!(request.body.contains("\"stream\":true"));
 }
 
+#[tokio::test]
+async fn stream_message_parses_sse_events_with_thinking_blocks() {
+    let state = Arc::new(Mutex::new(Vec::<CapturedRequest>::new()));
+    let sse = concat!(
+        "event: message_start\n",
+        "data: {\"type\":\"message_start\",\"message\":{\"id\":\"msg_stream_thinking\",\"type\":\"message\",\"role\":\"assistant\",\"content\":[],\"model\":\"claude-3-7-sonnet-latest\",\"stop_reason\":null,\"stop_sequence\":null,\"usage\":{\"input_tokens\":8,\"output_tokens\":0}}}\n\n",
+        "event: content_block_start\n",
+        "data: {\"type\":\"content_block_start\",\"index\":0,\"content_block\":{\"type\":\"thinking\",\"thinking\":\"\"}}\n\n",
+        "event: content_block_delta\n",
+        "data: {\"type\":\"content_block_delta\",\"index\":0,\"delta\":{\"type\":\"thinking_delta\",\"thinking\":\"step 1\"}}\n\n",
+        "event: content_block_delta\n",
+        "data: {\"type\":\"content_block_delta\",\"index\":0,\"delta\":{\"type\":\"signature_delta\",\"signature\":\"sig_123\"}}\n\n",
+        "event: content_block_stop\n",
+        "data: {\"type\":\"content_block_stop\",\"index\":0}\n\n",
+        "event: content_block_start\n",
+        "data: {\"type\":\"content_block_start\",\"index\":1,\"content_block\":{\"type\":\"text\",\"text\":\"Final answer\"}}\n\n",
+        "event: content_block_stop\n",
+        "data: {\"type\":\"content_block_stop\",\"index\":1}\n\n",
+        "event: message_delta\n",
+        "data: {\"type\":\"message_delta\",\"delta\":{\"stop_reason\":\"end_turn\",\"stop_sequence\":null},\"usage\":{\"input_tokens\":8,\"output_tokens\":1}}\n\n",
+        "event: message_stop\n",
+        "data: {\"type\":\"message_stop\"}\n\n",
+        "data: [DONE]\n\n"
+    );
+    let server = spawn_server(
+        state,
+        vec![http_response("200 OK", "text/event-stream", sse)],
+    )
+    .await;
+
+    let client = AnthropicClient::new("test-key").with_base_url(server.base_url());
+    let mut stream = client
+        .stream_message(&sample_request(false))
+        .await
+        .expect("stream should start");
+
+    let mut events = Vec::new();
+    while let Some(event) = stream
+        .next_event()
+        .await
+        .expect("stream event should parse")
+    {
+        events.push(event);
+    }
+
+    assert_eq!(events.len(), 9);
+    assert!(matches!(
+        &events[1],
+        StreamEvent::ContentBlockStart(ContentBlockStartEvent {
+            content_block: OutputContentBlock::Thinking { thinking, signature },
+            ..
+        }) if thinking.is_empty() && signature.is_none()
+    ));
+    assert!(matches!(
+        &events[2],
+        StreamEvent::ContentBlockDelta(ContentBlockDeltaEvent {
+            delta: ContentBlockDelta::ThinkingDelta { thinking },
+            ..
+        }) if thinking == "step 1"
+    ));
+    assert!(matches!(
+        &events[3],
+        StreamEvent::ContentBlockDelta(ContentBlockDeltaEvent {
+            delta: ContentBlockDelta::SignatureDelta { signature },
+            ..
+        }) if signature == "sig_123"
+    ));
+    assert!(matches!(
+        &events[5],
+        StreamEvent::ContentBlockStart(ContentBlockStartEvent {
+            content_block: OutputContentBlock::Text { text },
+            ..
+        }) if text == "Final answer"
+    ));
+    assert!(matches!(events[6], StreamEvent::ContentBlockStop(_)));
+    assert!(matches!(events[7], StreamEvent::MessageDelta(_)));
+    assert!(matches!(events[8], StreamEvent::MessageStop(_)));
+}
+
 #[tokio::test]
 async fn retries_retryable_failures_before_succeeding() {
     let state = Arc::new(Mutex::new(Vec::<CapturedRequest>::new()));

rust/crates/commands/Cargo.toml

@@ -9,4 +9,5 @@ publish.workspace = true
 workspace = true
 
 [dependencies]
+plugins = { path = "../plugins" }
 runtime = { path = "../runtime" }

rust/crates/commands/src/lib.rs

@@ -1,3 +1,9 @@
+use std::collections::BTreeMap;
+use std::env;
+use std::fs;
+use std::path::{Path, PathBuf};
+
+use plugins::{PluginError, PluginManager, PluginSummary};
 use runtime::{compact_session, CompactionConfig, Session};
 
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -33,6 +39,7 @@ impl CommandRegistry {
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub struct SlashCommandSpec {
     pub name: &'static str,
+    pub aliases: &'static [&'static str],
     pub summary: &'static str,
     pub argument_hint: Option<&'static str>,
     pub resume_supported: bool,
@@ -90,7 +97,7 @@ const SLASH_COMMAND_SPECS: &[SlashCommandSpec] = &[
     SlashCommandSpec {
         name: "config",
         summary: "Inspect Claude config files or merged sections",
-        argument_hint: Some("[env|hooks|model]"),
+        argument_hint: Some("[env|hooks|model|plugins]"),
         resume_supported: true,
     },
     SlashCommandSpec {
@@ -171,6 +178,14 @@ const SLASH_COMMAND_SPECS: &[SlashCommandSpec] = &[
         argument_hint: Some("[list|switch <session-id>]"),
         resume_supported: false,
     },
+    SlashCommandSpec {
+        name: "plugins",
+        summary: "List or manage plugins",
+        argument_hint: Some(
+            "[list|install <path>|enable <name>|disable <name>|uninstall <id>|update <id>]",
+        ),
+        resume_supported: false,
+    },
 ];
 
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -222,6 +237,10 @@ pub enum SlashCommand {
         action: Option<String>,
         target: Option<String>,
     },
+    Plugins {
+        action: Option<String>,
+        target: Option<String>,
+    },
     Unknown(String),
 }
 
@@ -283,6 +302,13 @@ impl SlashCommand {
                 action: parts.next().map(ToOwned::to_owned),
                 target: parts.next().map(ToOwned::to_owned),
             },
+            "plugins" => Self::Plugins {
+                action: parts.next().map(ToOwned::to_owned),
+                target: {
+                    let remainder = parts.collect::<Vec<_>>().join(" ");
+                    (!remainder.is_empty()).then_some(remainder)
+                },
+            },
             other => Self::Unknown(other.to_string()),
         })
     }
@@ -337,6 +363,176 @@ pub struct SlashCommandResult {
     pub session: Session,
 }
 
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct PluginsCommandResult {
+    pub message: String,
+    pub reload_runtime: bool,
+}
+
+#[allow(clippy::too_many_lines)]
+pub fn handle_plugins_slash_command(
+    action: Option<&str>,
+    target: Option<&str>,
+    manager: &mut PluginManager,
+) -> Result<PluginsCommandResult, PluginError> {
+    match action {
+        None | Some("list") => Ok(PluginsCommandResult {
+            message: render_plugins_report(&manager.list_installed_plugins()?),
+            reload_runtime: false,
+        }),
+        Some("install") => {
+            let Some(target) = target else {
+                return Ok(PluginsCommandResult {
+                    message: "Usage: /plugins install <path>".to_string(),
+                    reload_runtime: false,
+                });
+            };
+            let install = manager.install(target)?;
+            let plugin = manager
+                .list_installed_plugins()?
+                .into_iter()
+                .find(|plugin| plugin.metadata.id == install.plugin_id);
+            Ok(PluginsCommandResult {
+                message: render_plugin_install_report(&install.plugin_id, plugin.as_ref()),
+                reload_runtime: true,
+            })
+        }
+        Some("enable") => {
+            let Some(target) = target else {
+                return Ok(PluginsCommandResult {
+                    message: "Usage: /plugins enable <name>".to_string(),
+                    reload_runtime: false,
+                });
+            };
+            let plugin = resolve_plugin_target(manager, target)?;
+            manager.enable(&plugin.metadata.id)?;
+            Ok(PluginsCommandResult {
+                message: format!(
+                    "Plugins\n  Result           enabled {}\n  Name             {}\n  Version          {}\n  Status           enabled",
+                    plugin.metadata.id, plugin.metadata.name, plugin.metadata.version
+                ),
+                reload_runtime: true,
+            })
+        }
+        Some("disable") => {
+            let Some(target) = target else {
+                return Ok(PluginsCommandResult {
+                    message: "Usage: /plugins disable <name>".to_string(),
+                    reload_runtime: false,
+                });
+            };
+            let plugin = resolve_plugin_target(manager, target)?;
+            manager.disable(&plugin.metadata.id)?;
+            Ok(PluginsCommandResult {
+                message: format!(
+                    "Plugins\n  Result           disabled {}\n  Name             {}\n  Version          {}\n  Status           disabled",
+                    plugin.metadata.id, plugin.metadata.name, plugin.metadata.version
+                ),
+                reload_runtime: true,
+            })
+        }
+        Some("uninstall") => {
+            let Some(target) = target else {
+                return Ok(PluginsCommandResult {
+                    message: "Usage: /plugins uninstall <plugin-id>".to_string(),
+                    reload_runtime: false,
+                });
+            };
+            manager.uninstall(target)?;
+            Ok(PluginsCommandResult {
+                message: format!("Plugins\n  Result           uninstalled {target}"),
+                reload_runtime: true,
+            })
+        }
+        Some("update") => {
+            let Some(target) = target else {
+                return Ok(PluginsCommandResult {
+                    message: "Usage: /plugins update <plugin-id>".to_string(),
+                    reload_runtime: false,
+                });
+            };
+            let update = manager.update(target)?;
+            let plugin = manager
+                .list_installed_plugins()?
+                .into_iter()
+                .find(|plugin| plugin.metadata.id == update.plugin_id);
+            Ok(PluginsCommandResult {
+                message: format!(
+                    "Plugins\n  Result           updated {}\n  Name             {}\n  Old version      {}\n  New version      {}\n  Status           {}",
+                    update.plugin_id,
+                    plugin
+                        .as_ref()
+                        .map_or_else(|| update.plugin_id.clone(), |plugin| plugin.metadata.name.clone()),
+                    update.old_version,
+                    update.new_version,
+                    plugin
+                        .as_ref()
+                        .map_or("unknown", |plugin| if plugin.enabled { "enabled" } else { "disabled" }),
+                ),
+                reload_runtime: true,
+            })
+        }
+        Some(other) => Ok(PluginsCommandResult {
+            message: format!(
+                "Unknown /plugins action '{other}'. Use list, install, enable, disable, uninstall, or update."
+            ),
+            reload_runtime: false,
+        }),
+    }
+}
+
+#[must_use]
+pub fn render_plugins_report(plugins: &[PluginSummary]) -> String {
+    let mut lines = vec!["Plugins".to_string()];
+    if plugins.is_empty() {
+        lines.push("  No plugins installed.".to_string());
+        return lines.join("\n");
+    }
+    for plugin in plugins {
+        let enabled = if plugin.enabled {
+            "enabled"
+        } else {
+            "disabled"
+        };
+        lines.push(format!(
+            "  {name:<20} v{version:<10} {enabled}",
+            name = plugin.metadata.name,
+            version = plugin.metadata.version,
+        ));
+    }
+    lines.join("\n")
+}
+
+fn render_plugin_install_report(plugin_id: &str, plugin: Option<&PluginSummary>) -> String {
+    let name = plugin.map_or(plugin_id, |plugin| plugin.metadata.name.as_str());
+    let version = plugin.map_or("unknown", |plugin| plugin.metadata.version.as_str());
+    let enabled = plugin.is_some_and(|plugin| plugin.enabled);
+    format!(
+        "Plugins\n  Result           installed {plugin_id}\n  Name             {name}\n  Version          {version}\n  Status           {}",
+        if enabled { "enabled" } else { "disabled" }
+    )
+}
+
+fn resolve_plugin_target(
+    manager: &PluginManager,
+    target: &str,
+) -> Result<PluginSummary, PluginError> {
+    let mut matches = manager
+        .list_installed_plugins()?
+        .into_iter()
+        .filter(|plugin| plugin.metadata.id == target || plugin.metadata.name == target)
+        .collect::<Vec<_>>();
+    match matches.len() {
+        1 => Ok(matches.remove(0)),
+        0 => Err(PluginError::NotFound(format!(
+            "plugin `{target}` is not installed or discoverable"
+        ))),
+        _ => Err(PluginError::InvalidManifest(format!(
+            "plugin name `{target}` is ambiguous; use the full plugin id"
+        ))),
+    }
+}
+
 #[must_use]
 pub fn handle_slash_command(
     input: &str,
@@ -383,6 +579,7 @@ pub fn handle_slash_command(
         | SlashCommand::Version
         | SlashCommand::Export { .. }
         | SlashCommand::Session { .. }
+        | SlashCommand::Plugins { .. }
         | SlashCommand::Unknown(_) => None,
     }
 }
@@ -390,11 +587,49 @@ pub fn handle_slash_command(
 #[cfg(test)]
 mod tests {
     use super::{
-        handle_slash_command, render_slash_command_help, resume_supported_slash_commands,
-        slash_command_specs, SlashCommand,
+        handle_plugins_slash_command, handle_slash_command, load_agents_from_roots,
+        load_skills_from_roots, render_agents_report, render_plugins_report, render_skills_report,
+        render_slash_command_help, resume_supported_slash_commands, slash_command_specs,
+        DefinitionSource, SlashCommand,
     };
+    use plugins::{PluginKind, PluginManager, PluginManagerConfig, PluginMetadata, PluginSummary};
     use runtime::{CompactionConfig, ContentBlock, ConversationMessage, MessageRole, Session};
+    use std::fs;
+    use std::path::{Path, PathBuf};
+    use std::time::{SystemTime, UNIX_EPOCH};
 
+    fn temp_dir(label: &str) -> PathBuf {
+        let nanos = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .expect("time should be after epoch")
+            .as_nanos();
+        std::env::temp_dir().join(format!("commands-plugin-{label}-{nanos}"))
+    }
+
+    fn write_external_plugin(root: &Path, name: &str, version: &str) {
+        fs::create_dir_all(root.join(".claude-plugin")).expect("manifest dir");
+        fs::write(
+            root.join(".claude-plugin").join("plugin.json"),
+            format!(
+                "{{\n  \"name\": \"{name}\",\n  \"version\": \"{version}\",\n  \"description\": \"commands plugin\"\n}}"
+            ),
+        )
+        .expect("write manifest");
+    }
+
+    fn write_bundled_plugin(root: &Path, name: &str, version: &str, default_enabled: bool) {
+        fs::create_dir_all(root.join(".claude-plugin")).expect("manifest dir");
+        fs::write(
+            root.join(".claude-plugin").join("plugin.json"),
+            format!(
+                "{{\n  \"name\": \"{name}\",\n  \"version\": \"{version}\",\n  \"description\": \"bundled commands plugin\",\n  \"defaultEnabled\": {}\n}}",
+                if default_enabled { "true" } else { "false" }
+            ),
+        )
+        .expect("write bundled manifest");
+    }
+
+    #[allow(clippy::too_many_lines)]
     #[test]
     fn parses_supported_slash_commands() {
         assert_eq!(SlashCommand::parse("/help"), Some(SlashCommand::Help));
@@ -492,6 +727,34 @@ mod tests {
                 target: Some("abc123".to_string())
             })
         );
+        assert_eq!(
+            SlashCommand::parse("/plugins install demo"),
+            Some(SlashCommand::Plugins {
+                action: Some("install".to_string()),
+                target: Some("demo".to_string())
+            })
+        );
+        assert_eq!(
+            SlashCommand::parse("/plugins list"),
+            Some(SlashCommand::Plugins {
+                action: Some("list".to_string()),
+                target: None
+            })
+        );
+        assert_eq!(
+            SlashCommand::parse("/plugins enable demo"),
+            Some(SlashCommand::Plugins {
+                action: Some("enable".to_string()),
+                target: Some("demo".to_string())
+            })
+        );
+        assert_eq!(
+            SlashCommand::parse("/plugins disable demo"),
+            Some(SlashCommand::Plugins {
+                action: Some("disable".to_string()),
+                target: Some("demo".to_string())
+            })
+        );
     }
 
     #[test]
@@ -513,14 +776,17 @@ mod tests {
         assert!(help.contains("/clear [--confirm]"));
         assert!(help.contains("/cost"));
         assert!(help.contains("/resume <session-path>"));
-        assert!(help.contains("/config [env|hooks|model]"));
+        assert!(help.contains("/config [env|hooks|model|plugins]"));
         assert!(help.contains("/memory"));
         assert!(help.contains("/init"));
         assert!(help.contains("/diff"));
         assert!(help.contains("/version"));
         assert!(help.contains("/export [file]"));
         assert!(help.contains("/session [list|switch <session-id>]"));
-        assert_eq!(slash_command_specs().len(), 22);
+        assert!(help.contains(
+            "/plugins [list|install <path>|enable <name>|disable <name>|uninstall <id>|update <id>]"
+        ));
+        assert_eq!(slash_command_specs().len(), 23);
         assert_eq!(resume_supported_slash_commands().len(), 11);
     }
 
@@ -618,5 +884,221 @@ mod tests {
         assert!(
             handle_slash_command("/session list", &session, CompactionConfig::default()).is_none()
         );
+        assert!(
+            handle_slash_command("/plugins list", &session, CompactionConfig::default()).is_none()
+        );
+    }
+
+    #[test]
+    fn renders_plugins_report_with_name_version_and_status() {
+        let rendered = render_plugins_report(&[
+            PluginSummary {
+                metadata: PluginMetadata {
+                    id: "demo@external".to_string(),
+                    name: "demo".to_string(),
+                    version: "1.2.3".to_string(),
+                    description: "demo plugin".to_string(),
+                    kind: PluginKind::External,
+                    source: "demo".to_string(),
+                    default_enabled: false,
+                    root: None,
+                },
+                enabled: true,
+            },
+            PluginSummary {
+                metadata: PluginMetadata {
+                    id: "sample@external".to_string(),
+                    name: "sample".to_string(),
+                    version: "0.9.0".to_string(),
+                    description: "sample plugin".to_string(),
+                    kind: PluginKind::External,
+                    source: "sample".to_string(),
+                    default_enabled: false,
+                    root: None,
+                },
+                enabled: false,
+            },
+        ]);
+
+        assert!(rendered.contains("demo"));
+        assert!(rendered.contains("v1.2.3"));
+        assert!(rendered.contains("enabled"));
+        assert!(rendered.contains("sample"));
+        assert!(rendered.contains("v0.9.0"));
+        assert!(rendered.contains("disabled"));
+    }
+
+    #[test]
+    fn lists_agents_from_project_and_user_roots() {
+        let workspace = temp_dir("agents-workspace");
+        let project_agents = workspace.join(".codex").join("agents");
+        let user_home = temp_dir("agents-home");
+        let user_agents = user_home.join(".codex").join("agents");
+
+        write_agent(
+            &project_agents,
+            "planner",
+            "Project planner",
+            "gpt-5.4",
+            "medium",
+        );
+        write_agent(
+            &user_agents,
+            "planner",
+            "User planner",
+            "gpt-5.4-mini",
+            "high",
+        );
+        write_agent(
+            &user_agents,
+            "verifier",
+            "Verification agent",
+            "gpt-5.4-mini",
+            "high",
+        );
+
+        let roots = vec![
+            (DefinitionSource::ProjectCodex, project_agents),
+            (DefinitionSource::UserCodex, user_agents),
+        ];
+        let report = render_agents_report(
+            &load_agents_from_roots(&roots).expect("agent roots should load"),
+        );
+
+        assert!(report.contains("Agents"));
+        assert!(report.contains("2 active agents"));
+        assert!(report.contains("Project (.codex):"));
+        assert!(report.contains("planner · Project planner · gpt-5.4 · medium"));
+        assert!(report.contains("User (~/.codex):"));
+        assert!(report.contains("(shadowed by Project (.codex)) planner · User planner"));
+        assert!(report.contains("verifier · Verification agent · gpt-5.4-mini · high"));
+
+        let _ = fs::remove_dir_all(workspace);
+        let _ = fs::remove_dir_all(user_home);
+    }
+
+    #[test]
+    fn lists_skills_from_project_and_user_roots() {
+        let workspace = temp_dir("skills-workspace");
+        let project_skills = workspace.join(".codex").join("skills");
+        let user_home = temp_dir("skills-home");
+        let user_skills = user_home.join(".codex").join("skills");
+
+        write_skill(&project_skills, "plan", "Project planning guidance");
+        write_skill(&user_skills, "plan", "User planning guidance");
+        write_skill(&user_skills, "help", "Help guidance");
+
+        let roots = vec![
+            (DefinitionSource::ProjectCodex, project_skills),
+            (DefinitionSource::UserCodex, user_skills),
+        ];
+        let report = render_skills_report(
+            &load_skills_from_roots(&roots).expect("skill roots should load"),
+        );
+
+        assert!(report.contains("Skills"));
+        assert!(report.contains("2 available skills"));
+        assert!(report.contains("Project (.codex):"));
+        assert!(report.contains("plan · Project planning guidance"));
+        assert!(report.contains("User (~/.codex):"));
+        assert!(report.contains("(shadowed by Project (.codex)) plan · User planning guidance"));
+        assert!(report.contains("help · Help guidance"));
+
+        let _ = fs::remove_dir_all(workspace);
+        let _ = fs::remove_dir_all(user_home);
+    }
+
+    #[test]
+    fn installs_plugin_from_path_and_lists_it() {
+        let config_home = temp_dir("home");
+        let source_root = temp_dir("source");
+        write_external_plugin(&source_root, "demo", "1.0.0");
+
+        let mut manager = PluginManager::new(PluginManagerConfig::new(&config_home));
+        let install = handle_plugins_slash_command(
+            Some("install"),
+            Some(source_root.to_str().expect("utf8 path")),
+            &mut manager,
+        )
+        .expect("install command should succeed");
+        assert!(install.reload_runtime);
+        assert!(install.message.contains("installed demo@external"));
+        assert!(install.message.contains("Name             demo"));
+        assert!(install.message.contains("Version          1.0.0"));
+        assert!(install.message.contains("Status           enabled"));
+
+        let list = handle_plugins_slash_command(Some("list"), None, &mut manager)
+            .expect("list command should succeed");
+        assert!(!list.reload_runtime);
+        assert!(list.message.contains("demo"));
+        assert!(list.message.contains("v1.0.0"));
+        assert!(list.message.contains("enabled"));
+
+        let _ = fs::remove_dir_all(config_home);
+        let _ = fs::remove_dir_all(source_root);
+    }
+
+    #[test]
+    fn enables_and_disables_plugin_by_name() {
+        let config_home = temp_dir("toggle-home");
+        let source_root = temp_dir("toggle-source");
+        write_external_plugin(&source_root, "demo", "1.0.0");
+
+        let mut manager = PluginManager::new(PluginManagerConfig::new(&config_home));
+        handle_plugins_slash_command(
+            Some("install"),
+            Some(source_root.to_str().expect("utf8 path")),
+            &mut manager,
+        )
+        .expect("install command should succeed");
+
+        let disable = handle_plugins_slash_command(Some("disable"), Some("demo"), &mut manager)
+            .expect("disable command should succeed");
+        assert!(disable.reload_runtime);
+        assert!(disable.message.contains("disabled demo@external"));
+        assert!(disable.message.contains("Name             demo"));
+        assert!(disable.message.contains("Status           disabled"));
+
+        let list = handle_plugins_slash_command(Some("list"), None, &mut manager)
+            .expect("list command should succeed");
+        assert!(list.message.contains("demo"));
+        assert!(list.message.contains("disabled"));
+
+        let enable = handle_plugins_slash_command(Some("enable"), Some("demo"), &mut manager)
+            .expect("enable command should succeed");
+        assert!(enable.reload_runtime);
+        assert!(enable.message.contains("enabled demo@external"));
+        assert!(enable.message.contains("Name             demo"));
+        assert!(enable.message.contains("Status           enabled"));
+
+        let list = handle_plugins_slash_command(Some("list"), None, &mut manager)
+            .expect("list command should succeed");
+        assert!(list.message.contains("demo"));
+        assert!(list.message.contains("enabled"));
+
+        let _ = fs::remove_dir_all(config_home);
+        let _ = fs::remove_dir_all(source_root);
+    }
+
+    #[test]
+    fn lists_auto_installed_bundled_plugins_with_status() {
+        let config_home = temp_dir("bundled-home");
+        let bundled_root = temp_dir("bundled-root");
+        let bundled_plugin = bundled_root.join("starter");
+        write_bundled_plugin(&bundled_plugin, "starter", "0.1.0", false);
+
+        let mut config = PluginManagerConfig::new(&config_home);
+        config.bundled_root = Some(bundled_root.clone());
+        let mut manager = PluginManager::new(config);
+
+        let list = handle_plugins_slash_command(Some("list"), None, &mut manager)
+            .expect("list command should succeed");
+        assert!(!list.reload_runtime);
+        assert!(list.message.contains("starter"));
+        assert!(list.message.contains("v0.1.0"));
+        assert!(list.message.contains("disabled"));
+
+        let _ = fs::remove_dir_all(config_home);
+        let _ = fs::remove_dir_all(bundled_root);
     }
 }

rust/crates/compat-harness/src/lib.rs

@@ -74,11 +74,7 @@ fn upstream_repo_candidates(primary_repo_root: &Path) -> Vec<PathBuf> {
         candidates.push(ancestor.join("clawd-code"));
     }
 
-    candidates.push(
-        primary_repo_root
-            .join("reference-source")
-            .join("claw-code"),
-    );
+    candidates.push(primary_repo_root.join("reference-source").join("claw-code"));
     candidates.push(primary_repo_root.join("vendor").join("claw-code"));
 
     let mut deduped = Vec::new();

rust/crates/plugins/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "plugins"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+publish.workspace = true
+
+[dependencies]
+serde = { version = "1", features = ["derive"] }
+serde_json = "1"
+
+[lints]
+workspace = true

rust/crates/plugins/bundled/example-bundled/.claude-plugin/plugin.json

@@ -0,0 +1,10 @@
+{
+  "name": "example-bundled",
+  "version": "0.1.0",
+  "description": "Example bundled plugin scaffold for the Rust plugin system",
+  "defaultEnabled": false,
+  "hooks": {
+    "PreToolUse": ["./hooks/pre.sh"],
+    "PostToolUse": ["./hooks/post.sh"]
+  }
+}

rust/crates/plugins/bundled/example-bundled/hooks/post.sh

@@ -0,0 +1,2 @@
+#!/bin/sh
+printf '%s\n' 'example bundled post hook'

rust/crates/plugins/bundled/example-bundled/hooks/pre.sh

@@ -0,0 +1,2 @@
+#!/bin/sh
+printf '%s\n' 'example bundled pre hook'

rust/crates/plugins/bundled/sample-hooks/.claude-plugin/plugin.json

@@ -0,0 +1,10 @@
+{
+  "name": "sample-hooks",
+  "version": "0.1.0",
+  "description": "Bundled sample plugin scaffold for hook integration tests.",
+  "defaultEnabled": false,
+  "hooks": {
+    "PreToolUse": ["./hooks/pre.sh"],
+    "PostToolUse": ["./hooks/post.sh"]
+  }
+}

rust/crates/plugins/bundled/sample-hooks/hooks/post.sh

@@ -0,0 +1,2 @@
+#!/bin/sh
+printf 'sample bundled post hook'

rust/crates/plugins/bundled/sample-hooks/hooks/pre.sh

@@ -0,0 +1,2 @@
+#!/bin/sh
+printf 'sample bundled pre hook'

rust/crates/plugins/src/hooks.rs

@@ -0,0 +1,395 @@
+use std::ffi::OsStr;
+use std::path::Path;
+use std::process::Command;
+
+use serde_json::json;
+
+use crate::{PluginError, PluginHooks, PluginRegistry};
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum HookEvent {
+    PreToolUse,
+    PostToolUse,
+}
+
+impl HookEvent {
+    fn as_str(self) -> &'static str {
+        match self {
+            Self::PreToolUse => "PreToolUse",
+            Self::PostToolUse => "PostToolUse",
+        }
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub struct HookRunResult {
+    denied: bool,
+    messages: Vec<String>,
+}
+
+impl HookRunResult {
+    #[must_use]
+    pub fn allow(messages: Vec<String>) -> Self {
+        Self {
+            denied: false,
+            messages,
+        }
+    }
+
+    #[must_use]
+    pub fn is_denied(&self) -> bool {
+        self.denied
+    }
+
+    #[must_use]
+    pub fn messages(&self) -> &[String] {
+        &self.messages
+    }
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Default)]
+pub struct HookRunner {
+    hooks: PluginHooks,
+}
+
+impl HookRunner {
+    #[must_use]
+    pub fn new(hooks: PluginHooks) -> Self {
+        Self { hooks }
+    }
+
+    pub fn from_registry(plugin_registry: &PluginRegistry) -> Result<Self, PluginError> {
+        Ok(Self::new(plugin_registry.aggregated_hooks()?))
+    }
+
+    #[must_use]
+    pub fn run_pre_tool_use(&self, tool_name: &str, tool_input: &str) -> HookRunResult {
+        self.run_commands(
+            HookEvent::PreToolUse,
+            &self.hooks.pre_tool_use,
+            tool_name,
+            tool_input,
+            None,
+            false,
+        )
+    }
+
+    #[must_use]
+    pub fn run_post_tool_use(
+        &self,
+        tool_name: &str,
+        tool_input: &str,
+        tool_output: &str,
+        is_error: bool,
+    ) -> HookRunResult {
+        self.run_commands(
+            HookEvent::PostToolUse,
+            &self.hooks.post_tool_use,
+            tool_name,
+            tool_input,
+            Some(tool_output),
+            is_error,
+        )
+    }
+
+    fn run_commands(
+        &self,
+        event: HookEvent,
+        commands: &[String],
+        tool_name: &str,
+        tool_input: &str,
+        tool_output: Option<&str>,
+        is_error: bool,
+    ) -> HookRunResult {
+        if commands.is_empty() {
+            return HookRunResult::allow(Vec::new());
+        }
+
+        let payload = json!({
+            "hook_event_name": event.as_str(),
+            "tool_name": tool_name,
+            "tool_input": parse_tool_input(tool_input),
+            "tool_input_json": tool_input,
+            "tool_output": tool_output,
+            "tool_result_is_error": is_error,
+        })
+        .to_string();
+
+        let mut messages = Vec::new();
+
+        for command in commands {
+            match self.run_command(
+                command,
+                event,
+                tool_name,
+                tool_input,
+                tool_output,
+                is_error,
+                &payload,
+            ) {
+                HookCommandOutcome::Allow { message } => {
+                    if let Some(message) = message {
+                        messages.push(message);
+                    }
+                }
+                HookCommandOutcome::Deny { message } => {
+                    messages.push(message.unwrap_or_else(|| {
+                        format!("{} hook denied tool `{tool_name}`", event.as_str())
+                    }));
+                    return HookRunResult {
+                        denied: true,
+                        messages,
+                    };
+                }
+                HookCommandOutcome::Warn { message } => messages.push(message),
+            }
+        }
+
+        HookRunResult::allow(messages)
+    }
+
+    #[allow(clippy::too_many_arguments, clippy::unused_self)]
+    fn run_command(
+        &self,
+        command: &str,
+        event: HookEvent,
+        tool_name: &str,
+        tool_input: &str,
+        tool_output: Option<&str>,
+        is_error: bool,
+        payload: &str,
+    ) -> HookCommandOutcome {
+        let mut child = shell_command(command);
+        child.stdin(std::process::Stdio::piped());
+        child.stdout(std::process::Stdio::piped());
+        child.stderr(std::process::Stdio::piped());
+        child.env("HOOK_EVENT", event.as_str());
+        child.env("HOOK_TOOL_NAME", tool_name);
+        child.env("HOOK_TOOL_INPUT", tool_input);
+        child.env("HOOK_TOOL_IS_ERROR", if is_error { "1" } else { "0" });
+        if let Some(tool_output) = tool_output {
+            child.env("HOOK_TOOL_OUTPUT", tool_output);
+        }
+
+        match child.output_with_stdin(payload.as_bytes()) {
+            Ok(output) => {
+                let stdout = String::from_utf8_lossy(&output.stdout).trim().to_string();
+                let stderr = String::from_utf8_lossy(&output.stderr).trim().to_string();
+                let message = (!stdout.is_empty()).then_some(stdout);
+                match output.status.code() {
+                    Some(0) => HookCommandOutcome::Allow { message },
+                    Some(2) => HookCommandOutcome::Deny { message },
+                    Some(code) => HookCommandOutcome::Warn {
+                        message: format_hook_warning(
+                            command,
+                            code,
+                            message.as_deref(),
+                            stderr.as_str(),
+                        ),
+                    },
+                    None => HookCommandOutcome::Warn {
+                        message: format!(
+                            "{} hook `{command}` terminated by signal while handling `{tool_name}`",
+                            event.as_str()
+                        ),
+                    },
+                }
+            }
+            Err(error) => HookCommandOutcome::Warn {
+                message: format!(
+                    "{} hook `{command}` failed to start for `{tool_name}`: {error}",
+                    event.as_str()
+                ),
+            },
+        }
+    }
+}
+
+enum HookCommandOutcome {
+    Allow { message: Option<String> },
+    Deny { message: Option<String> },
+    Warn { message: String },
+}
+
+fn parse_tool_input(tool_input: &str) -> serde_json::Value {
+    serde_json::from_str(tool_input).unwrap_or_else(|_| json!({ "raw": tool_input }))
+}
+
+fn format_hook_warning(command: &str, code: i32, stdout: Option<&str>, stderr: &str) -> String {
+    let mut message =
+        format!("Hook `{command}` exited with status {code}; allowing tool execution to continue");
+    if let Some(stdout) = stdout.filter(|stdout| !stdout.is_empty()) {
+        message.push_str(": ");
+        message.push_str(stdout);
+    } else if !stderr.is_empty() {
+        message.push_str(": ");
+        message.push_str(stderr);
+    }
+    message
+}
+
+fn shell_command(command: &str) -> CommandWithStdin {
+    #[cfg(windows)]
+    let command_builder = {
+        let mut command_builder = Command::new("cmd");
+        command_builder.arg("/C").arg(command);
+        CommandWithStdin::new(command_builder)
+    };
+
+    #[cfg(not(windows))]
+    let command_builder = if Path::new(command).exists() {
+        let mut command_builder = Command::new("sh");
+        command_builder.arg(command);
+        CommandWithStdin::new(command_builder)
+    } else {
+        let mut command_builder = Command::new("sh");
+        command_builder.arg("-lc").arg(command);
+        CommandWithStdin::new(command_builder)
+    };
+
+    command_builder
+}
+
+struct CommandWithStdin {
+    command: Command,
+}
+
+impl CommandWithStdin {
+    fn new(command: Command) -> Self {
+        Self { command }
+    }
+
+    fn stdin(&mut self, cfg: std::process::Stdio) -> &mut Self {
+        self.command.stdin(cfg);
+        self
+    }
+
+    fn stdout(&mut self, cfg: std::process::Stdio) -> &mut Self {
+        self.command.stdout(cfg);
+        self
+    }
+
+    fn stderr(&mut self, cfg: std::process::Stdio) -> &mut Self {
+        self.command.stderr(cfg);
+        self
+    }
+
+    fn env<K, V>(&mut self, key: K, value: V) -> &mut Self
+    where
+        K: AsRef<OsStr>,
+        V: AsRef<OsStr>,
+    {
+        self.command.env(key, value);
+        self
+    }
+
+    fn output_with_stdin(&mut self, stdin: &[u8]) -> std::io::Result<std::process::Output> {
+        let mut child = self.command.spawn()?;
+        if let Some(mut child_stdin) = child.stdin.take() {
+            use std::io::Write as _;
+            child_stdin.write_all(stdin)?;
+        }
+        child.wait_with_output()
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{HookRunResult, HookRunner};
+    use crate::{PluginManager, PluginManagerConfig};
+    use std::fs;
+    use std::path::{Path, PathBuf};
+    use std::time::{SystemTime, UNIX_EPOCH};
+
+    fn temp_dir(label: &str) -> PathBuf {
+        let nanos = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .expect("time should be after epoch")
+            .as_nanos();
+        std::env::temp_dir().join(format!("plugins-hook-runner-{label}-{nanos}"))
+    }
+
+    fn write_hook_plugin(root: &Path, name: &str, pre_message: &str, post_message: &str) {
+        fs::create_dir_all(root.join(".claude-plugin")).expect("manifest dir");
+        fs::create_dir_all(root.join("hooks")).expect("hooks dir");
+        fs::write(
+            root.join("hooks").join("pre.sh"),
+            format!("#!/bin/sh\nprintf '%s\\n' '{pre_message}'\n"),
+        )
+        .expect("write pre hook");
+        fs::write(
+            root.join("hooks").join("post.sh"),
+            format!("#!/bin/sh\nprintf '%s\\n' '{post_message}'\n"),
+        )
+        .expect("write post hook");
+        fs::write(
+            root.join(".claude-plugin").join("plugin.json"),
+            format!(
+                "{{\n  \"name\": \"{name}\",\n  \"version\": \"1.0.0\",\n  \"description\": \"hook plugin\",\n  \"hooks\": {{\n    \"PreToolUse\": [\"./hooks/pre.sh\"],\n    \"PostToolUse\": [\"./hooks/post.sh\"]\n  }}\n}}"
+            ),
+        )
+        .expect("write plugin manifest");
+    }
+
+    #[test]
+    fn collects_and_runs_hooks_from_enabled_plugins() {
+        let config_home = temp_dir("config");
+        let first_source_root = temp_dir("source-a");
+        let second_source_root = temp_dir("source-b");
+        write_hook_plugin(
+            &first_source_root,
+            "first",
+            "plugin pre one",
+            "plugin post one",
+        );
+        write_hook_plugin(
+            &second_source_root,
+            "second",
+            "plugin pre two",
+            "plugin post two",
+        );
+
+        let mut manager = PluginManager::new(PluginManagerConfig::new(&config_home));
+        manager
+            .install(first_source_root.to_str().expect("utf8 path"))
+            .expect("first plugin install should succeed");
+        manager
+            .install(second_source_root.to_str().expect("utf8 path"))
+            .expect("second plugin install should succeed");
+        let registry = manager.plugin_registry().expect("registry should build");
+
+        let runner = HookRunner::from_registry(&registry).expect("plugin hooks should load");
+
+        assert_eq!(
+            runner.run_pre_tool_use("Read", r#"{"path":"README.md"}"#),
+            HookRunResult::allow(vec![
+                "plugin pre one".to_string(),
+                "plugin pre two".to_string(),
+            ])
+        );
+        assert_eq!(
+            runner.run_post_tool_use("Read", r#"{"path":"README.md"}"#, "ok", false),
+            HookRunResult::allow(vec![
+                "plugin post one".to_string(),
+                "plugin post two".to_string(),
+            ])
+        );
+
+        let _ = fs::remove_dir_all(config_home);
+        let _ = fs::remove_dir_all(first_source_root);
+        let _ = fs::remove_dir_all(second_source_root);
+    }
+
+    #[test]
+    fn pre_tool_use_denies_when_plugin_hook_exits_two() {
+        let runner = HookRunner::new(crate::PluginHooks {
+            pre_tool_use: vec!["printf 'blocked by plugin'; exit 2".to_string()],
+            post_tool_use: Vec::new(),
+        });
+
+        let result = runner.run_pre_tool_use("Bash", r#"{"command":"pwd"}"#);
+
+        assert!(result.is_denied());
+        assert_eq!(result.messages(), &["blocked by plugin".to_string()]);
+    }
+}

rust/crates/runtime/Cargo.toml

@@ -8,6 +8,7 @@ publish.workspace = true
 [dependencies]
 sha2 = "0.10"
 glob = "0.3"
+plugins = { path = "../plugins" }
 regex = "1"
 serde = { version = "1", features = ["derive"] }
 serde_json = "1"

rust/crates/runtime/src/compact.rs

@@ -1,5 +1,10 @@
 use crate::session::{ContentBlock, ConversationMessage, MessageRole, Session};
 
+const COMPACT_CONTINUATION_PREAMBLE: &str =
+    "This session is being continued from a previous conversation that ran out of context. The summary below covers the earlier portion of the conversation.\n\n";
+const COMPACT_RECENT_MESSAGES_NOTE: &str = "Recent messages are preserved verbatim.";
+const COMPACT_DIRECT_RESUME_INSTRUCTION: &str = "Continue the conversation from where it left off without asking the user any further questions. Resume directly — do not acknowledge the summary, do not recap what was happening, and do not preface with continuation text.";
+
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
 pub struct CompactionConfig {
     pub preserve_recent_messages: usize,
@@ -30,8 +35,15 @@ pub fn estimate_session_tokens(session: &Session) -> usize {
 
 #[must_use]
 pub fn should_compact(session: &Session, config: CompactionConfig) -> bool {
-    session.messages.len() > config.preserve_recent_messages
-        && estimate_session_tokens(session) >= config.max_estimated_tokens
+    let start = compacted_summary_prefix_len(session);
+    let compactable = &session.messages[start..];
+
+    compactable.len() > config.preserve_recent_messages
+        && compactable
+            .iter()
+            .map(estimate_message_tokens)
+            .sum::<usize>()
+            >= config.max_estimated_tokens
 }
 
 #[must_use]
@@ -56,16 +68,18 @@ pub fn get_compact_continuation_message(
     recent_messages_preserved: bool,
 ) -> String {
     let mut base = format!(
-        "This session is being continued from a previous conversation that ran out of context. The summary below covers the earlier portion of the conversation.\n\n{}",
+        "{COMPACT_CONTINUATION_PREAMBLE}{}",
         format_compact_summary(summary)
     );
 
     if recent_messages_preserved {
-        base.push_str("\n\nRecent messages are preserved verbatim.");
+        base.push_str("\n\n");
+        base.push_str(COMPACT_RECENT_MESSAGES_NOTE);
     }
 
     if suppress_follow_up_questions {
-        base.push_str("\nContinue the conversation from where it left off without asking the user any further questions. Resume directly — do not acknowledge the summary, do not recap what was happening, and do not preface with continuation text.");
+        base.push('\n');
+        base.push_str(COMPACT_DIRECT_RESUME_INSTRUCTION);
     }
 
     base
@@ -82,13 +96,19 @@ pub fn compact_session(session: &Session, config: CompactionConfig) -> Compactio
         };
     }
 
+    let existing_summary = session
+        .messages
+        .first()
+        .and_then(extract_existing_compacted_summary);
+    let compacted_prefix_len = usize::from(existing_summary.is_some());
     let keep_from = session
         .messages
         .len()
         .saturating_sub(config.preserve_recent_messages);
-    let removed = &session.messages[..keep_from];
+    let removed = &session.messages[compacted_prefix_len..keep_from];
     let preserved = session.messages[keep_from..].to_vec();
-    let summary = summarize_messages(removed);
+    let summary =
+        merge_compact_summaries(existing_summary.as_deref(), &summarize_messages(removed));
     let formatted_summary = format_compact_summary(&summary);
     let continuation = get_compact_continuation_message(&summary, true, !preserved.is_empty());
 
@@ -110,6 +130,16 @@ pub fn compact_session(session: &Session, config: CompactionConfig) -> Compactio
     }
 }
 
+fn compacted_summary_prefix_len(session: &Session) -> usize {
+    usize::from(
+        session
+            .messages
+            .first()
+            .and_then(extract_existing_compacted_summary)
+            .is_some(),
+    )
+}
+
 fn summarize_messages(messages: &[ConversationMessage]) -> String {
     let user_messages = messages
         .iter()
@@ -197,6 +227,41 @@ fn summarize_messages(messages: &[ConversationMessage]) -> String {
     lines.join("\n")
 }
 
+fn merge_compact_summaries(existing_summary: Option<&str>, new_summary: &str) -> String {
+    let Some(existing_summary) = existing_summary else {
+        return new_summary.to_string();
+    };
+
+    let previous_highlights = extract_summary_highlights(existing_summary);
+    let new_formatted_summary = format_compact_summary(new_summary);
+    let new_highlights = extract_summary_highlights(&new_formatted_summary);
+    let new_timeline = extract_summary_timeline(&new_formatted_summary);
+
+    let mut lines = vec!["<summary>".to_string(), "Conversation summary:".to_string()];
+
+    if !previous_highlights.is_empty() {
+        lines.push("- Previously compacted context:".to_string());
+        lines.extend(
+            previous_highlights
+                .into_iter()
+                .map(|line| format!("  {line}")),
+        );
+    }
+
+    if !new_highlights.is_empty() {
+        lines.push("- Newly compacted context:".to_string());
+        lines.extend(new_highlights.into_iter().map(|line| format!("  {line}")));
+    }
+
+    if !new_timeline.is_empty() {
+        lines.push("- Key timeline:".to_string());
+        lines.extend(new_timeline.into_iter().map(|line| format!("  {line}")));
+    }
+
+    lines.push("</summary>".to_string());
+    lines.join("\n")
+}
+
 fn summarize_block(block: &ContentBlock) -> String {
     let raw = match block {
         ContentBlock::Text { text } => text.clone(),
@@ -374,11 +439,71 @@ fn collapse_blank_lines(content: &str) -> String {
     result
 }
 
+fn extract_existing_compacted_summary(message: &ConversationMessage) -> Option<String> {
+    if message.role != MessageRole::System {
+        return None;
+    }
+
+    let text = first_text_block(message)?;
+    let summary = text.strip_prefix(COMPACT_CONTINUATION_PREAMBLE)?;
+    let summary = summary
+        .split_once(&format!("\n\n{COMPACT_RECENT_MESSAGES_NOTE}"))
+        .map_or(summary, |(value, _)| value);
+    let summary = summary
+        .split_once(&format!("\n{COMPACT_DIRECT_RESUME_INSTRUCTION}"))
+        .map_or(summary, |(value, _)| value);
+    Some(summary.trim().to_string())
+}
+
+fn extract_summary_highlights(summary: &str) -> Vec<String> {
+    let mut lines = Vec::new();
+    let mut in_timeline = false;
+
+    for line in format_compact_summary(summary).lines() {
+        let trimmed = line.trim_end();
+        if trimmed.is_empty() || trimmed == "Summary:" || trimmed == "Conversation summary:" {
+            continue;
+        }
+        if trimmed == "- Key timeline:" {
+            in_timeline = true;
+            continue;
+        }
+        if in_timeline {
+            continue;
+        }
+        lines.push(trimmed.to_string());
+    }
+
+    lines
+}
+
+fn extract_summary_timeline(summary: &str) -> Vec<String> {
+    let mut lines = Vec::new();
+    let mut in_timeline = false;
+
+    for line in format_compact_summary(summary).lines() {
+        let trimmed = line.trim_end();
+        if trimmed == "- Key timeline:" {
+            in_timeline = true;
+            continue;
+        }
+        if !in_timeline {
+            continue;
+        }
+        if trimmed.is_empty() {
+            break;
+        }
+        lines.push(trimmed.to_string());
+    }
+
+    lines
+}
+
 #[cfg(test)]
 mod tests {
     use super::{
         collect_key_files, compact_session, estimate_session_tokens, format_compact_summary,
-        infer_pending_work, should_compact, CompactionConfig,
+        get_compact_continuation_message, infer_pending_work, should_compact, CompactionConfig,
     };
     use crate::session::{ContentBlock, ConversationMessage, MessageRole, Session};
 
@@ -453,6 +578,98 @@ mod tests {
         );
     }
 
+    #[test]
+    fn keeps_previous_compacted_context_when_compacting_again() {
+        let initial_session = Session {
+            version: 1,
+            messages: vec![
+                ConversationMessage::user_text("Investigate rust/crates/runtime/src/compact.rs"),
+                ConversationMessage::assistant(vec![ContentBlock::Text {
+                    text: "I will inspect the compact flow.".to_string(),
+                }]),
+                ConversationMessage::user_text(
+                    "Also update rust/crates/runtime/src/conversation.rs",
+                ),
+                ConversationMessage::assistant(vec![ContentBlock::Text {
+                    text: "Next: preserve prior summary context during auto compact.".to_string(),
+                }]),
+            ],
+        };
+        let config = CompactionConfig {
+            preserve_recent_messages: 2,
+            max_estimated_tokens: 1,
+        };
+
+        let first = compact_session(&initial_session, config);
+        let mut follow_up_messages = first.compacted_session.messages.clone();
+        follow_up_messages.extend([
+            ConversationMessage::user_text("Please add regression tests for compaction."),
+            ConversationMessage::assistant(vec![ContentBlock::Text {
+                text: "Working on regression coverage now.".to_string(),
+            }]),
+        ]);
+
+        let second = compact_session(
+            &Session {
+                version: 1,
+                messages: follow_up_messages,
+            },
+            config,
+        );
+
+        assert!(second
+            .formatted_summary
+            .contains("Previously compacted context:"));
+        assert!(second
+            .formatted_summary
+            .contains("Scope: 2 earlier messages compacted"));
+        assert!(second
+            .formatted_summary
+            .contains("Newly compacted context:"));
+        assert!(second
+            .formatted_summary
+            .contains("Also update rust/crates/runtime/src/conversation.rs"));
+        assert!(matches!(
+            &second.compacted_session.messages[0].blocks[0],
+            ContentBlock::Text { text }
+                if text.contains("Previously compacted context:")
+                    && text.contains("Newly compacted context:")
+        ));
+        assert!(matches!(
+            &second.compacted_session.messages[1].blocks[0],
+            ContentBlock::Text { text } if text.contains("Please add regression tests for compaction.")
+        ));
+    }
+
+    #[test]
+    fn ignores_existing_compacted_summary_when_deciding_to_recompact() {
+        let summary = "<summary>Conversation summary:\n- Scope: earlier work preserved.\n- Key timeline:\n  - user: large preserved context\n</summary>";
+        let session = Session {
+            version: 1,
+            messages: vec![
+                ConversationMessage {
+                    role: MessageRole::System,
+                    blocks: vec![ContentBlock::Text {
+                        text: get_compact_continuation_message(summary, true, true),
+                    }],
+                    usage: None,
+                },
+                ConversationMessage::user_text("tiny"),
+                ConversationMessage::assistant(vec![ContentBlock::Text {
+                    text: "recent".to_string(),
+                }]),
+            ],
+        };
+
+        assert!(!should_compact(
+            &session,
+            CompactionConfig {
+                preserve_recent_messages: 2,
+                max_estimated_tokens: 1,
+            }
+        ));
+    }
+
     #[test]
     fn truncates_long_blocks_in_summary() {
         let summary = super::summarize_block(&ContentBlock::Text {

rust/crates/runtime/src/config.rs

@@ -35,9 +35,19 @@ pub struct RuntimeConfig {
     feature_config: RuntimeFeatureConfig,
 }
 
+#[derive(Debug, Clone, PartialEq, Eq, Default)]
+pub struct RuntimePluginConfig {
+    enabled_plugins: BTreeMap<String, bool>,
+    external_directories: Vec<String>,
+    install_root: Option<String>,
+    registry_path: Option<String>,
+    bundled_root: Option<String>,
+}
+
 #[derive(Debug, Clone, PartialEq, Eq, Default)]
 pub struct RuntimeFeatureConfig {
     hooks: RuntimeHookConfig,
+    plugins: RuntimePluginConfig,
     mcp: McpConfigCollection,
     oauth: Option<OAuthConfig>,
     model: Option<String>,
@@ -174,13 +184,15 @@ impl ConfigLoader {
     #[must_use]
     pub fn default_for(cwd: impl Into<PathBuf>) -> Self {
         let cwd = cwd.into();
-        let config_home = std::env::var_os("CLAUDE_CONFIG_HOME")
-            .map(PathBuf::from)
-            .or_else(|| std::env::var_os("HOME").map(|home| PathBuf::from(home).join(".claude")))
-            .unwrap_or_else(|| PathBuf::from(".claude"));
+        let config_home = default_config_home();
         Self { cwd, config_home }
     }
 
+    #[must_use]
+    pub fn config_home(&self) -> &Path {
+        &self.config_home
+    }
+
     #[must_use]
     pub fn discover(&self) -> Vec<ConfigEntry> {
         let user_legacy_path = self.config_home.parent().map_or_else(
@@ -229,6 +241,7 @@ impl ConfigLoader {
 
         let feature_config = RuntimeFeatureConfig {
             hooks: parse_optional_hooks_config(&merged_value)?,
+            plugins: parse_optional_plugin_config(&merged_value)?,
             mcp: McpConfigCollection {
                 servers: mcp_servers,
             },
@@ -291,6 +304,11 @@ impl RuntimeConfig {
         &self.feature_config.hooks
     }
 
+    #[must_use]
+    pub fn plugins(&self) -> &RuntimePluginConfig {
+        &self.feature_config.plugins
+    }
+
     #[must_use]
     pub fn oauth(&self) -> Option<&OAuthConfig> {
         self.feature_config.oauth.as_ref()
@@ -319,11 +337,22 @@ impl RuntimeFeatureConfig {
         self
     }
 
+    #[must_use]
+    pub fn with_plugins(mut self, plugins: RuntimePluginConfig) -> Self {
+        self.plugins = plugins;
+        self
+    }
+
     #[must_use]
     pub fn hooks(&self) -> &RuntimeHookConfig {
         &self.hooks
     }
 
+    #[must_use]
+    pub fn plugins(&self) -> &RuntimePluginConfig {
+        &self.plugins
+    }
+
     #[must_use]
     pub fn mcp(&self) -> &McpConfigCollection {
         &self.mcp
@@ -350,6 +379,53 @@ impl RuntimeFeatureConfig {
     }
 }
 
+impl RuntimePluginConfig {
+    #[must_use]
+    pub fn enabled_plugins(&self) -> &BTreeMap<String, bool> {
+        &self.enabled_plugins
+    }
+
+    #[must_use]
+    pub fn external_directories(&self) -> &[String] {
+        &self.external_directories
+    }
+
+    #[must_use]
+    pub fn install_root(&self) -> Option<&str> {
+        self.install_root.as_deref()
+    }
+
+    #[must_use]
+    pub fn registry_path(&self) -> Option<&str> {
+        self.registry_path.as_deref()
+    }
+
+    #[must_use]
+    pub fn bundled_root(&self) -> Option<&str> {
+        self.bundled_root.as_deref()
+    }
+
+    pub fn set_plugin_state(&mut self, plugin_id: String, enabled: bool) {
+        self.enabled_plugins.insert(plugin_id, enabled);
+    }
+
+    #[must_use]
+    pub fn state_for(&self, plugin_id: &str, default_enabled: bool) -> bool {
+        self.enabled_plugins
+            .get(plugin_id)
+            .copied()
+            .unwrap_or(default_enabled)
+    }
+}
+
+#[must_use]
+pub fn default_config_home() -> PathBuf {
+    std::env::var_os("CLAUDE_CONFIG_HOME")
+        .map(PathBuf::from)
+        .or_else(|| std::env::var_os("HOME").map(|home| PathBuf::from(home).join(".claude")))
+        .unwrap_or_else(|| PathBuf::from(".claude"))
+}
+
 impl RuntimeHookConfig {
     #[must_use]
     pub fn new(pre_tool_use: Vec<String>, post_tool_use: Vec<String>) -> Self {
@@ -368,6 +444,18 @@ impl RuntimeHookConfig {
     pub fn post_tool_use(&self) -> &[String] {
         &self.post_tool_use
     }
+
+    #[must_use]
+    pub fn merged(&self, other: &Self) -> Self {
+        let mut merged = self.clone();
+        merged.extend(other);
+        merged
+    }
+
+    pub fn extend(&mut self, other: &Self) {
+        extend_unique(&mut self.pre_tool_use, other.pre_tool_use());
+        extend_unique(&mut self.post_tool_use, other.post_tool_use());
+    }
 }
 
 impl McpConfigCollection {
@@ -484,6 +572,36 @@ fn parse_optional_hooks_config(root: &JsonValue) -> Result<RuntimeHookConfig, Co
     })
 }
 
+fn parse_optional_plugin_config(root: &JsonValue) -> Result<RuntimePluginConfig, ConfigError> {
+    let Some(object) = root.as_object() else {
+        return Ok(RuntimePluginConfig::default());
+    };
+
+    let mut config = RuntimePluginConfig::default();
+    if let Some(enabled_plugins) = object.get("enabledPlugins") {
+        config.enabled_plugins = parse_bool_map(enabled_plugins, "merged settings.enabledPlugins")?;
+    }
+
+    let Some(plugins_value) = object.get("plugins") else {
+        return Ok(config);
+    };
+    let plugins = expect_object(plugins_value, "merged settings.plugins")?;
+
+    if let Some(enabled_value) = plugins.get("enabled") {
+        config.enabled_plugins = parse_bool_map(enabled_value, "merged settings.plugins.enabled")?;
+    }
+    config.external_directories =
+        optional_string_array(plugins, "externalDirectories", "merged settings.plugins")?
+            .unwrap_or_default();
+    config.install_root =
+        optional_string(plugins, "installRoot", "merged settings.plugins")?.map(str::to_string);
+    config.registry_path =
+        optional_string(plugins, "registryPath", "merged settings.plugins")?.map(str::to_string);
+    config.bundled_root =
+        optional_string(plugins, "bundledRoot", "merged settings.plugins")?.map(str::to_string);
+    Ok(config)
+}
+
 fn parse_optional_permission_mode(
     root: &JsonValue,
 ) -> Result<Option<ResolvedPermissionMode>, ConfigError> {
@@ -716,6 +834,24 @@ fn optional_u16(
     }
 }
 
+fn parse_bool_map(value: &JsonValue, context: &str) -> Result<BTreeMap<String, bool>, ConfigError> {
+    let Some(map) = value.as_object() else {
+        return Err(ConfigError::Parse(format!(
+            "{context}: expected JSON object"
+        )));
+    };
+    map.iter()
+        .map(|(key, value)| {
+            value
+                .as_bool()
+                .map(|enabled| (key.clone(), enabled))
+                .ok_or_else(|| {
+                    ConfigError::Parse(format!("{context}: field {key} must be a boolean"))
+                })
+        })
+        .collect()
+}
+
 fn optional_string_array(
     object: &BTreeMap<String, JsonValue>,
     key: &str,
@@ -790,6 +926,18 @@ fn deep_merge_objects(
     }
 }
 
+fn extend_unique(target: &mut Vec<String>, values: &[String]) {
+    for value in values {
+        push_unique(target, value.clone());
+    }
+}
+
+fn push_unique(target: &mut Vec<String>, value: String) {
+    if !target.iter().any(|existing| existing == &value) {
+        target.push(value);
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::{
@@ -1033,6 +1181,96 @@ mod tests {
         fs::remove_dir_all(root).expect("cleanup temp dir");
     }
 
+    #[test]
+    fn parses_plugin_config_from_enabled_plugins() {
+        let root = temp_dir();
+        let cwd = root.join("project");
+        let home = root.join("home").join(".claude");
+        fs::create_dir_all(cwd.join(".claude")).expect("project config dir");
+        fs::create_dir_all(&home).expect("home config dir");
+
+        fs::write(
+            home.join("settings.json"),
+            r#"{
+              "enabledPlugins": {
+                "tool-guard@builtin": true,
+                "sample-plugin@external": false
+              }
+            }"#,
+        )
+        .expect("write user settings");
+
+        let loaded = ConfigLoader::new(&cwd, &home)
+            .load()
+            .expect("config should load");
+
+        assert_eq!(
+            loaded.plugins().enabled_plugins().get("tool-guard@builtin"),
+            Some(&true)
+        );
+        assert_eq!(
+            loaded
+                .plugins()
+                .enabled_plugins()
+                .get("sample-plugin@external"),
+            Some(&false)
+        );
+
+        fs::remove_dir_all(root).expect("cleanup temp dir");
+    }
+
+    #[test]
+    fn parses_plugin_config() {
+        let root = temp_dir();
+        let cwd = root.join("project");
+        let home = root.join("home").join(".claude");
+        fs::create_dir_all(cwd.join(".claude")).expect("project config dir");
+        fs::create_dir_all(&home).expect("home config dir");
+
+        fs::write(
+            home.join("settings.json"),
+            r#"{
+              "enabledPlugins": {
+                "core-helpers@builtin": true
+              },
+              "plugins": {
+                "externalDirectories": ["./external-plugins"],
+                "installRoot": "plugin-cache/installed",
+                "registryPath": "plugin-cache/installed.json",
+                "bundledRoot": "./bundled-plugins"
+              }
+            }"#,
+        )
+        .expect("write plugin settings");
+
+        let loaded = ConfigLoader::new(&cwd, &home)
+            .load()
+            .expect("config should load");
+
+        assert_eq!(
+            loaded
+                .plugins()
+                .enabled_plugins()
+                .get("core-helpers@builtin"),
+            Some(&true)
+        );
+        assert_eq!(
+            loaded.plugins().external_directories(),
+            &["./external-plugins".to_string()]
+        );
+        assert_eq!(
+            loaded.plugins().install_root(),
+            Some("plugin-cache/installed")
+        );
+        assert_eq!(
+            loaded.plugins().registry_path(),
+            Some("plugin-cache/installed.json")
+        );
+        assert_eq!(loaded.plugins().bundled_root(), Some("./bundled-plugins"));
+
+        fs::remove_dir_all(root).expect("cleanup temp dir");
+    }
+
     #[test]
     fn rejects_invalid_mcp_server_shapes() {
         let root = temp_dir();

rust/crates/runtime/src/conversation.rs

@@ -1,11 +1,13 @@
 use std::collections::BTreeMap;
 use std::fmt::{Display, Formatter};
 
+use plugins::{HookRunner as PluginHookRunner, PluginRegistry};
+
 use crate::compact::{
     compact_session, estimate_session_tokens, CompactionConfig, CompactionResult,
 };
 use crate::config::RuntimeFeatureConfig;
-use crate::hooks::{HookRunResult, HookRunner};
+use crate::hooks::HookRunner;
 use crate::permissions::{PermissionOutcome, PermissionPolicy, PermissionPrompter};
 use crate::session::{ContentBlock, ConversationMessage, Session};
 use crate::usage::{TokenUsage, UsageTracker};
@@ -107,6 +109,24 @@ pub struct ConversationRuntime<C, T> {
     usage_tracker: UsageTracker,
     hook_runner: HookRunner,
     auto_compaction_input_tokens_threshold: u32,
+    plugin_hook_runner: Option<PluginHookRunner>,
+    plugin_registry: Option<PluginRegistry>,
+    plugins_shutdown: bool,
+}
+
+impl<C, T> ConversationRuntime<C, T> {
+    fn shutdown_registered_plugins(&mut self) -> Result<(), RuntimeError> {
+        if self.plugins_shutdown {
+            return Ok(());
+        }
+        if let Some(registry) = &self.plugin_registry {
+            registry
+                .shutdown()
+                .map_err(|error| RuntimeError::new(format!("plugin shutdown failed: {error}")))?;
+        }
+        self.plugins_shutdown = true;
+        Ok(())
+    }
 }
 
 impl<C, T> ConversationRuntime<C, T>
@@ -133,6 +153,7 @@ where
     }
 
     #[must_use]
+    #[allow(clippy::needless_pass_by_value)]
     pub fn new_with_features(
         session: Session,
         api_client: C,
@@ -152,9 +173,42 @@ where
             usage_tracker,
             hook_runner: HookRunner::from_feature_config(&feature_config),
             auto_compaction_input_tokens_threshold: auto_compaction_threshold_from_env(),
+            plugin_hook_runner: None,
+            plugin_registry: None,
+            plugins_shutdown: false,
         }
     }
 
+    #[allow(clippy::needless_pass_by_value)]
+    pub fn new_with_plugins(
+        session: Session,
+        api_client: C,
+        tool_executor: T,
+        permission_policy: PermissionPolicy,
+        system_prompt: Vec<String>,
+        feature_config: RuntimeFeatureConfig,
+        plugin_registry: PluginRegistry,
+    ) -> Result<Self, RuntimeError> {
+        let plugin_hook_runner =
+            PluginHookRunner::from_registry(&plugin_registry).map_err(|error| {
+                RuntimeError::new(format!("plugin hook registration failed: {error}"))
+            })?;
+        plugin_registry
+            .initialize()
+            .map_err(|error| RuntimeError::new(format!("plugin initialization failed: {error}")))?;
+        let mut runtime = Self::new_with_features(
+            session,
+            api_client,
+            tool_executor,
+            permission_policy,
+            system_prompt,
+            feature_config,
+        );
+        runtime.plugin_hook_runner = Some(plugin_hook_runner);
+        runtime.plugin_registry = Some(plugin_registry);
+        Ok(runtime)
+    }
+
     #[must_use]
     pub fn with_max_iterations(mut self, max_iterations: usize) -> Self {
         self.max_iterations = max_iterations;
@@ -167,6 +221,7 @@ where
         self
     }
 
+    #[allow(clippy::too_many_lines)]
     pub fn run_turn(
         &mut self,
         user_input: impl Into<String>,
@@ -179,6 +234,7 @@ where
         let mut assistant_messages = Vec::new();
         let mut tool_results = Vec::new();
         let mut iterations = 0;
+        let mut max_turn_input_tokens = 0;
 
         loop {
             iterations += 1;
@@ -195,6 +251,7 @@ where
             let events = self.api_client.stream(request)?;
             let (assistant_message, usage) = build_assistant_message(events)?;
             if let Some(usage) = usage {
+                max_turn_input_tokens = max_turn_input_tokens.max(usage.input_tokens);
                 self.usage_tracker.record(usage);
             }
             let pending_tool_uses = assistant_message
@@ -231,35 +288,74 @@ where
                             ConversationMessage::tool_result(
                                 tool_use_id,
                                 tool_name,
-                                format_hook_message(&pre_hook_result, &deny_message),
+                                format_hook_message(pre_hook_result.messages(), &deny_message),
                                 true,
                             )
                         } else {
-                            let (mut output, mut is_error) =
-                                match self.tool_executor.execute(&tool_name, &input) {
-                                    Ok(output) => (output, false),
-                                    Err(error) => (error.to_string(), true),
-                                };
-                            output = merge_hook_feedback(pre_hook_result.messages(), output, false);
+                            let plugin_pre_hook_result =
+                                self.run_plugin_pre_tool_use(&tool_name, &input);
+                            if plugin_pre_hook_result.is_denied() {
+                                let deny_message =
+                                    format!("PreToolUse hook denied tool `{tool_name}`");
+                                let mut messages = pre_hook_result.messages().to_vec();
+                                messages.extend(plugin_pre_hook_result.messages().iter().cloned());
+                                ConversationMessage::tool_result(
+                                    tool_use_id,
+                                    tool_name,
+                                    format_hook_message(&messages, &deny_message),
+                                    true,
+                                )
+                            } else {
+                                let (mut output, mut is_error) =
+                                    match self.tool_executor.execute(&tool_name, &input) {
+                                        Ok(output) => (output, false),
+                                        Err(error) => (error.to_string(), true),
+                                    };
+                                output =
+                                    merge_hook_feedback(pre_hook_result.messages(), output, false);
+                                output = merge_hook_feedback(
+                                    plugin_pre_hook_result.messages(),
+                                    output,
+                                    false,
+                                );
 
-                            let post_hook_result = self
-                                .hook_runner
-                                .run_post_tool_use(&tool_name, &input, &output, is_error);
-                            if post_hook_result.is_denied() {
-                                is_error = true;
+                                let hook_output = output.clone();
+                                let post_hook_result = self.hook_runner.run_post_tool_use(
+                                    &tool_name,
+                                    &input,
+                                    &hook_output,
+                                    is_error,
+                                );
+                                let plugin_post_hook_result = self.run_plugin_post_tool_use(
+                                    &tool_name,
+                                    &input,
+                                    &hook_output,
+                                    is_error,
+                                );
+                                if post_hook_result.is_denied() {
+                                    is_error = true;
+                                }
+                                if plugin_post_hook_result.is_denied() {
+                                    is_error = true;
+                                }
+                                output = merge_hook_feedback(
+                                    post_hook_result.messages(),
+                                    output,
+                                    post_hook_result.is_denied(),
+                                );
+                                output = merge_hook_feedback(
+                                    plugin_post_hook_result.messages(),
+                                    output,
+                                    plugin_post_hook_result.is_denied(),
+                                );
+
+                                ConversationMessage::tool_result(
+                                    tool_use_id,
+                                    tool_name,
+                                    output,
+                                    is_error,
+                                )
                             }
-                            output = merge_hook_feedback(
-                                post_hook_result.messages(),
-                                output,
-                                post_hook_result.is_denied(),
-                            );
-
-                            ConversationMessage::tool_result(
-                                tool_use_id,
-                                tool_name,
-                                output,
-                                is_error,
-                            )
                         }
                     }
                     PermissionOutcome::Deny { reason } => {
@@ -271,7 +367,7 @@ where
             }
         }
 
-        let auto_compaction = self.maybe_auto_compact();
+        let auto_compaction = self.maybe_auto_compact(max_turn_input_tokens);
 
         Ok(TurnSummary {
             assistant_messages,
@@ -303,21 +399,45 @@ where
     }
 
     #[must_use]
-    pub fn into_session(self) -> Session {
-        self.session
+    pub fn into_session(mut self) -> Session {
+        let _ = self.shutdown_registered_plugins();
+        std::mem::take(&mut self.session)
     }
 
-    fn maybe_auto_compact(&mut self) -> Option<AutoCompactionEvent> {
-        if self.usage_tracker.cumulative_usage().input_tokens
-            < self.auto_compaction_input_tokens_threshold
-        {
+    pub fn shutdown_plugins(&mut self) -> Result<(), RuntimeError> {
+        self.shutdown_registered_plugins()
+    }
+
+    fn run_plugin_pre_tool_use(&self, tool_name: &str, input: &str) -> plugins::HookRunResult {
+        self.plugin_hook_runner.as_ref().map_or_else(
+            || plugins::HookRunResult::allow(Vec::new()),
+            |runner| runner.run_pre_tool_use(tool_name, input),
+        )
+    }
+
+    fn run_plugin_post_tool_use(
+        &self,
+        tool_name: &str,
+        input: &str,
+        output: &str,
+        is_error: bool,
+    ) -> plugins::HookRunResult {
+        self.plugin_hook_runner.as_ref().map_or_else(
+            || plugins::HookRunResult::allow(Vec::new()),
+            |runner| runner.run_post_tool_use(tool_name, input, output, is_error),
+        )
+    }
+
+    fn maybe_auto_compact(&mut self, turn_input_tokens: u32) -> Option<AutoCompactionEvent> {
+        if turn_input_tokens < self.auto_compaction_input_tokens_threshold {
             return None;
         }
 
         let result = compact_session(
             &self.session,
             CompactionConfig {
-                max_estimated_tokens: 0,
+                max_estimated_tokens: usize::try_from(self.auto_compaction_input_tokens_threshold)
+                    .unwrap_or(usize::MAX),
                 ..CompactionConfig::default()
             },
         );
@@ -333,6 +453,12 @@ where
     }
 }
 
+impl<C, T> Drop for ConversationRuntime<C, T> {
+    fn drop(&mut self) {
+        let _ = self.shutdown_registered_plugins();
+    }
+}
+
 #[must_use]
 pub fn auto_compaction_threshold_from_env() -> u32 {
     parse_auto_compaction_threshold(
@@ -397,11 +523,11 @@ fn flush_text_block(text: &mut String, blocks: &mut Vec<ContentBlock>) {
     }
 }
 
-fn format_hook_message(result: &HookRunResult, fallback: &str) -> String {
-    if result.messages().is_empty() {
+fn format_hook_message(messages: &[String], fallback: &str) -> String {
+    if messages.is_empty() {
         fallback.to_string()
     } else {
-        result.messages().join("\n")
+        messages.join("\n")
     }
 }
 
@@ -471,7 +597,13 @@ mod tests {
     use crate::prompt::{ProjectContext, SystemPromptBuilder};
     use crate::session::{ContentBlock, MessageRole, Session};
     use crate::usage::TokenUsage;
+    use plugins::{PluginManager, PluginManagerConfig};
+    use std::fs;
+    #[cfg(unix)]
+    use std::os::unix::fs::PermissionsExt;
+    use std::path::Path;
     use std::path::PathBuf;
+    use std::time::{SystemTime, UNIX_EPOCH};
 
     struct ScriptedApiClient {
         call_count: usize,
@@ -533,6 +665,68 @@ mod tests {
         }
     }
 
+    fn temp_dir(label: &str) -> PathBuf {
+        let nanos = SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .expect("time should be after epoch")
+            .as_nanos();
+        std::env::temp_dir().join(format!("runtime-plugin-{label}-{nanos}"))
+    }
+
+    fn write_lifecycle_plugin(root: &Path, name: &str) -> PathBuf {
+        fs::create_dir_all(root.join(".claude-plugin")).expect("manifest dir");
+        fs::create_dir_all(root.join("lifecycle")).expect("lifecycle dir");
+        let log_path = root.join("lifecycle.log");
+        fs::write(
+            root.join("lifecycle").join("init.sh"),
+            "#!/bin/sh\nprintf 'init\\n' >> lifecycle.log\n",
+        )
+        .expect("write init script");
+        fs::write(
+            root.join("lifecycle").join("shutdown.sh"),
+            "#!/bin/sh\nprintf 'shutdown\\n' >> lifecycle.log\n",
+        )
+        .expect("write shutdown script");
+        fs::write(
+            root.join(".claude-plugin").join("plugin.json"),
+            format!(
+                "{{\n  \"name\": \"{name}\",\n  \"version\": \"1.0.0\",\n  \"description\": \"runtime lifecycle plugin\",\n  \"lifecycle\": {{\n    \"Init\": [\"./lifecycle/init.sh\"],\n    \"Shutdown\": [\"./lifecycle/shutdown.sh\"]\n  }}\n}}"
+            ),
+        )
+        .expect("write plugin manifest");
+        log_path
+    }
+
+    fn write_hook_plugin(root: &Path, name: &str, pre_message: &str, post_message: &str) {
+        fs::create_dir_all(root.join(".claude-plugin")).expect("manifest dir");
+        fs::create_dir_all(root.join("hooks")).expect("hooks dir");
+        fs::write(
+            root.join("hooks").join("pre.sh"),
+            format!("#!/bin/sh\nprintf '%s\\n' '{pre_message}'\n"),
+        )
+        .expect("write pre hook");
+        fs::write(
+            root.join("hooks").join("post.sh"),
+            format!("#!/bin/sh\nprintf '%s\\n' '{post_message}'\n"),
+        )
+        .expect("write post hook");
+        #[cfg(unix)]
+        {
+            let exec_mode = fs::Permissions::from_mode(0o755);
+            fs::set_permissions(root.join("hooks").join("pre.sh"), exec_mode.clone())
+                .expect("chmod pre hook");
+            fs::set_permissions(root.join("hooks").join("post.sh"), exec_mode)
+                .expect("chmod post hook");
+        }
+        fs::write(
+            root.join(".claude-plugin").join("plugin.json"),
+            format!(
+                "{{\n  \"name\": \"{name}\",\n  \"version\": \"1.0.0\",\n  \"description\": \"runtime hook plugin\",\n  \"hooks\": {{\n    \"PreToolUse\": [\"./hooks/pre.sh\"],\n    \"PostToolUse\": [\"./hooks/post.sh\"]\n  }}\n}}"
+            ),
+        )
+        .expect("write plugin manifest");
+    }
+
     #[test]
     fn runs_user_to_tool_to_result_loop_end_to_end_and_tracks_usage() {
         let api_client = ScriptedApiClient { call_count: 0 };
@@ -761,7 +955,7 @@ mod tests {
             "post hook should preserve non-error result: {output:?}"
         );
         assert!(
-            output.contains("4"),
+            output.contains('4'),
             "tool output missing value: {output:?}"
         );
         assert!(
@@ -774,6 +968,153 @@ mod tests {
         );
     }
 
+    #[test]
+    fn initializes_and_shuts_down_plugins_with_runtime_lifecycle() {
+        let config_home = temp_dir("config");
+        let source_root = temp_dir("source");
+        let _ = write_lifecycle_plugin(&source_root, "runtime-lifecycle");
+
+        let mut manager = PluginManager::new(PluginManagerConfig::new(&config_home));
+        let install = manager
+            .install(source_root.to_str().expect("utf8 path"))
+            .expect("install should succeed");
+        let log_path = install.install_path.join("lifecycle.log");
+        let registry = manager.plugin_registry().expect("registry should load");
+
+        {
+            let runtime = ConversationRuntime::new_with_plugins(
+                Session::new(),
+                ScriptedApiClient { call_count: 0 },
+                StaticToolExecutor::new().register("add", |_input| Ok("4".to_string())),
+                PermissionPolicy::new(PermissionMode::WorkspaceWrite),
+                vec!["system".to_string()],
+                RuntimeFeatureConfig::default(),
+                registry,
+            )
+            .expect("runtime should initialize plugins");
+
+            let log = fs::read_to_string(&log_path).expect("init log should exist");
+            assert_eq!(log, "init\n");
+            drop(runtime);
+        }
+
+        let log = fs::read_to_string(&log_path).expect("shutdown log should exist");
+        assert_eq!(log, "init\nshutdown\n");
+
+        let _ = fs::remove_dir_all(config_home);
+        let _ = fs::remove_dir_all(source_root);
+    }
+
+    #[test]
+    fn executes_hooks_from_installed_plugins_during_tool_use() {
+        struct TwoCallApiClient {
+            calls: usize,
+        }
+
+        impl ApiClient for TwoCallApiClient {
+            fn stream(&mut self, request: ApiRequest) -> Result<Vec<AssistantEvent>, RuntimeError> {
+                self.calls += 1;
+                match self.calls {
+                    1 => Ok(vec![
+                        AssistantEvent::ToolUse {
+                            id: "tool-1".to_string(),
+                            name: "add".to_string(),
+                            input: r#"{"lhs":2,"rhs":2}"#.to_string(),
+                        },
+                        AssistantEvent::MessageStop,
+                    ]),
+                    2 => {
+                        assert!(request
+                            .messages
+                            .iter()
+                            .any(|message| message.role == MessageRole::Tool));
+                        Ok(vec![
+                            AssistantEvent::TextDelta("done".to_string()),
+                            AssistantEvent::MessageStop,
+                        ])
+                    }
+                    _ => Err(RuntimeError::new("unexpected extra API call")),
+                }
+            }
+        }
+
+        let config_home = temp_dir("hook-config");
+        let first_source_root = temp_dir("hook-source-a");
+        let second_source_root = temp_dir("hook-source-b");
+        write_hook_plugin(
+            &first_source_root,
+            "first",
+            "plugin pre one",
+            "plugin post one",
+        );
+        write_hook_plugin(
+            &second_source_root,
+            "second",
+            "plugin pre two",
+            "plugin post two",
+        );
+
+        let mut manager = PluginManager::new(PluginManagerConfig::new(&config_home));
+        manager
+            .install(first_source_root.to_str().expect("utf8 path"))
+            .expect("first plugin install should succeed");
+        manager
+            .install(second_source_root.to_str().expect("utf8 path"))
+            .expect("second plugin install should succeed");
+        let registry = manager.plugin_registry().expect("registry should load");
+
+        let mut runtime = ConversationRuntime::new_with_plugins(
+            Session::new(),
+            TwoCallApiClient { calls: 0 },
+            StaticToolExecutor::new().register("add", |_input| Ok("4".to_string())),
+            PermissionPolicy::new(PermissionMode::DangerFullAccess),
+            vec!["system".to_string()],
+            RuntimeFeatureConfig::default(),
+            registry,
+        )
+        .expect("runtime should load plugin hooks");
+
+        let summary = runtime
+            .run_turn("use add", None)
+            .expect("tool loop succeeds");
+
+        assert_eq!(summary.tool_results.len(), 1);
+        let ContentBlock::ToolResult {
+            is_error, output, ..
+        } = &summary.tool_results[0].blocks[0]
+        else {
+            panic!("expected tool result block");
+        };
+        assert!(
+            !*is_error,
+            "plugin hooks should not force an error: {output:?}"
+        );
+        assert!(
+            output.contains('4'),
+            "tool output missing value: {output:?}"
+        );
+        assert!(
+            output.contains("plugin pre one"),
+            "tool output missing first pre hook feedback: {output:?}"
+        );
+        assert!(
+            output.contains("plugin pre two"),
+            "tool output missing second pre hook feedback: {output:?}"
+        );
+        assert!(
+            output.contains("plugin post one"),
+            "tool output missing first post hook feedback: {output:?}"
+        );
+        assert!(
+            output.contains("plugin post two"),
+            "tool output missing second post hook feedback: {output:?}"
+        );
+
+        let _ = fs::remove_dir_all(config_home);
+        let _ = fs::remove_dir_all(first_source_root);
+        let _ = fs::remove_dir_all(second_source_root);
+    }
+
     #[test]
     fn reconstructs_usage_tracker_from_restored_session() {
         struct SimpleApi;
@@ -864,7 +1205,7 @@ mod tests {
     }
 
     #[test]
-    fn auto_compacts_when_cumulative_input_threshold_is_crossed() {
+    fn auto_compacts_when_turn_input_threshold_is_crossed() {
         struct SimpleApi;
         impl ApiClient for SimpleApi {
             fn stream(
@@ -887,13 +1228,13 @@ mod tests {
         let session = Session {
             version: 1,
             messages: vec![
-                crate::session::ConversationMessage::user_text("one"),
+                crate::session::ConversationMessage::user_text("one ".repeat(30_000)),
                 crate::session::ConversationMessage::assistant(vec![ContentBlock::Text {
-                    text: "two".to_string(),
+                    text: "two ".repeat(30_000),
                 }]),
-                crate::session::ConversationMessage::user_text("three"),
+                crate::session::ConversationMessage::user_text("three ".repeat(30_000)),
                 crate::session::ConversationMessage::assistant(vec![ContentBlock::Text {
-                    text: "four".to_string(),
+                    text: "four ".repeat(30_000),
                 }]),
             ],
         };
@@ -920,6 +1261,72 @@ mod tests {
         assert_eq!(runtime.session().messages[0].role, MessageRole::System);
     }
 
+    #[test]
+    fn auto_compaction_does_not_repeat_after_context_is_already_compacted() {
+        struct SequentialUsageApi {
+            call_count: usize,
+        }
+
+        impl ApiClient for SequentialUsageApi {
+            fn stream(
+                &mut self,
+                _request: ApiRequest,
+            ) -> Result<Vec<AssistantEvent>, RuntimeError> {
+                self.call_count += 1;
+                let input_tokens = if self.call_count == 1 { 120_000 } else { 64 };
+                Ok(vec![
+                    AssistantEvent::TextDelta("done".to_string()),
+                    AssistantEvent::Usage(TokenUsage {
+                        input_tokens,
+                        output_tokens: 4,
+                        cache_creation_input_tokens: 0,
+                        cache_read_input_tokens: 0,
+                    }),
+                    AssistantEvent::MessageStop,
+                ])
+            }
+        }
+
+        let session = Session {
+            version: 1,
+            messages: vec![
+                crate::session::ConversationMessage::user_text("one ".repeat(30_000)),
+                crate::session::ConversationMessage::assistant(vec![ContentBlock::Text {
+                    text: "two ".repeat(30_000),
+                }]),
+                crate::session::ConversationMessage::user_text("three ".repeat(30_000)),
+                crate::session::ConversationMessage::assistant(vec![ContentBlock::Text {
+                    text: "four ".repeat(30_000),
+                }]),
+            ],
+        };
+
+        let mut runtime = ConversationRuntime::new(
+            session,
+            SequentialUsageApi { call_count: 0 },
+            StaticToolExecutor::new(),
+            PermissionPolicy::new(PermissionMode::DangerFullAccess),
+            vec!["system".to_string()],
+        )
+        .with_auto_compaction_input_tokens_threshold(100_000);
+
+        let first = runtime
+            .run_turn("trigger", None)
+            .expect("first turn should succeed");
+        assert_eq!(
+            first.auto_compaction,
+            Some(AutoCompactionEvent {
+                removed_message_count: 2,
+            })
+        );
+
+        let second = runtime
+            .run_turn("continue", None)
+            .expect("second turn should succeed");
+        assert_eq!(second.auto_compaction, None);
+        assert_eq!(runtime.session().messages[0].role, MessageRole::System);
+    }
+
     #[test]
     fn skips_auto_compaction_below_threshold() {
         struct SimpleApi;

rust/crates/runtime/src/hooks.rs

@@ -1,4 +1,5 @@
 use std::ffi::OsStr;
+use std::path::Path;
 use std::process::Command;
 
 use serde_json::json;
@@ -149,6 +150,7 @@ impl HookRunner {
         HookRunResult::allow(messages)
     }
 
+    #[allow(clippy::too_many_arguments, clippy::unused_self)]
     fn run_command(
         &self,
         command: &str,
@@ -237,7 +239,11 @@ fn shell_command(command: &str) -> CommandWithStdin {
     };
 
     #[cfg(not(windows))]
-    let command_builder = {
+    let command_builder = if Path::new(command).exists() {
+        let mut command_builder = Command::new("sh");
+        command_builder.arg(command);
+        CommandWithStdin::new(command_builder)
+    } else {
         let mut command_builder = Command::new("sh");
         command_builder.arg("-lc").arg(command);
         CommandWithStdin::new(command_builder)

rust/crates/runtime/src/lib.rs

@@ -28,7 +28,7 @@ pub use config::{
     McpConfigCollection, McpOAuthConfig, McpRemoteServerConfig, McpSdkServerConfig,
     McpServerConfig, McpStdioServerConfig, McpTransport, McpWebSocketServerConfig, OAuthConfig,
     ResolvedPermissionMode, RuntimeConfig, RuntimeFeatureConfig, RuntimeHookConfig,
-    ScopedMcpServerConfig, CLAUDE_CODE_SETTINGS_SCHEMA_NAME,
+    RuntimePluginConfig, ScopedMcpServerConfig, CLAUDE_CODE_SETTINGS_SCHEMA_NAME,
 };
 pub use conversation::{
     auto_compaction_threshold_from_env, ApiClient, ApiRequest, AssistantEvent, AutoCompactionEvent,

rust/crates/runtime/src/prompt.rs

@@ -421,7 +421,7 @@ fn render_config_section(config: &RuntimeConfig) -> String {
     let mut lines = vec!["# Runtime config".to_string()];
     if config.loaded_entries().is_empty() {
         lines.extend(prepend_bullets(vec![
-            "No Claw Code settings files loaded.".to_string(),
+            "No Claw Code settings files loaded.".to_string()
         ]));
         return lines.join("\n");
     }

rust/crates/rusty-claude-cli/Cargo.toml

@@ -17,6 +17,7 @@ crossterm = "0.28"
 pulldown-cmark = "0.13"
 rustyline = "15"
 runtime = { path = "../runtime" }
+plugins = { path = "../plugins" }
 serde_json = "1"
 syntect = "5"
 tokio = { version = "1", features = ["rt-multi-thread", "time"] }

rust/crates/rusty-claude-cli/src/render.rs

@@ -286,7 +286,7 @@ impl TerminalRenderer {
     ) {
         match event {
             Event::Start(Tag::Heading { level, .. }) => {
-                self.start_heading(state, level as u8, output)
+                self.start_heading(state, level as u8, output);
             }
             Event::End(TagEnd::Paragraph) => output.push_str("\n\n"),
             Event::Start(Tag::BlockQuote(..)) => self.start_quote(state, output),
@@ -426,6 +426,7 @@ impl TerminalRenderer {
         }
     }
 
+    #[allow(clippy::unused_self)]
     fn start_heading(&self, state: &mut RenderState, level: u8, output: &mut String) {
         state.heading_level = Some(level);
         if !output.is_empty() {

rust/crates/tools/Cargo.toml

@@ -7,6 +7,7 @@ publish.workspace = true
 
 [dependencies]
 api = { path = "../api" }
+plugins = { path = "../plugins" }
 runtime = { path = "../runtime" }
 reqwest = { version = "0.12", default-features = false, features = ["blocking", "rustls-tls"] }
 serde = { version = "1", features = ["derive"] }

rust/crates/tools/src/lib.rs

@@ -8,12 +8,13 @@ use api::{
     MessageRequest, MessageResponse, OutputContentBlock, StreamEvent as ApiStreamEvent, ToolChoice,
     ToolDefinition, ToolResultContentBlock,
 };
+use plugins::{PluginManager, PluginManagerConfig, PluginTool};
 use reqwest::blocking::Client;
 use runtime::{
     edit_file, execute_bash, glob_search, grep_search, load_system_prompt, read_file, write_file,
-    ApiClient, ApiRequest, AssistantEvent, BashCommandInput, ContentBlock, ConversationMessage,
-    ConversationRuntime, GrepSearchInput, MessageRole, PermissionMode, PermissionPolicy,
-    RuntimeError, Session, TokenUsage, ToolError, ToolExecutor,
+    ApiClient, ApiRequest, AssistantEvent, BashCommandInput, ConfigLoader, ContentBlock,
+    ConversationMessage, ConversationRuntime, GrepSearchInput, MessageRole, PermissionMode,
+    PermissionPolicy, RuntimeConfig, RuntimeError, Session, TokenUsage, ToolError, ToolExecutor,
 };
 use serde::{Deserialize, Serialize};
 use serde_json::{json, Value};
@@ -55,6 +56,239 @@ pub struct ToolSpec {
     pub required_permission: PermissionMode,
 }
 
+#[derive(Debug, Clone, PartialEq)]
+pub struct RegisteredTool {
+    pub definition: ToolDefinition,
+    pub required_permission: PermissionMode,
+    handler: RegisteredToolHandler,
+}
+
+#[allow(clippy::large_enum_variant)]
+#[derive(Debug, Clone, PartialEq)]
+enum RegisteredToolHandler {
+    Builtin,
+    Plugin(PluginTool),
+}
+
+#[derive(Debug, Clone, PartialEq)]
+pub struct GlobalToolRegistry {
+    entries: Vec<RegisteredTool>,
+}
+
+impl GlobalToolRegistry {
+    #[must_use]
+    pub fn builtin() -> Self {
+        Self {
+            entries: mvp_tool_specs()
+                .into_iter()
+                .map(|spec| RegisteredTool {
+                    definition: ToolDefinition {
+                        name: spec.name.to_string(),
+                        description: Some(spec.description.to_string()),
+                        input_schema: spec.input_schema,
+                    },
+                    required_permission: spec.required_permission,
+                    handler: RegisteredToolHandler::Builtin,
+                })
+                .collect(),
+        }
+    }
+
+    pub fn with_plugin_tools(plugin_tools: Vec<PluginTool>) -> Result<Self, String> {
+        let mut registry = Self::builtin();
+        let mut seen = registry
+            .entries
+            .iter()
+            .map(|entry| {
+                (
+                    normalize_registry_tool_name(&entry.definition.name),
+                    entry.definition.name.clone(),
+                )
+            })
+            .collect::<BTreeMap<_, _>>();
+
+        for tool in plugin_tools {
+            let normalized = normalize_registry_tool_name(&tool.definition().name);
+            if let Some(existing) = seen.get(&normalized) {
+                return Err(format!(
+                    "plugin tool `{}` from `{}` conflicts with already-registered tool `{existing}`",
+                    tool.definition().name,
+                    tool.plugin_id()
+                ));
+            }
+            seen.insert(normalized, tool.definition().name.clone());
+            registry.entries.push(RegisteredTool {
+                definition: ToolDefinition {
+                    name: tool.definition().name.clone(),
+                    description: tool.definition().description.clone(),
+                    input_schema: tool.definition().input_schema.clone(),
+                },
+                required_permission: permission_mode_from_plugin_tool(tool.required_permission())?,
+                handler: RegisteredToolHandler::Plugin(tool),
+            });
+        }
+
+        Ok(registry)
+    }
+
+    #[must_use]
+    pub fn entries(&self) -> &[RegisteredTool] {
+        &self.entries
+    }
+
+    fn find_entry(&self, name: &str) -> Option<&RegisteredTool> {
+        let normalized = normalize_registry_tool_name(name);
+        self.entries.iter().find(|entry| {
+            normalize_registry_tool_name(entry.definition.name.as_str()) == normalized
+        })
+    }
+
+    #[must_use]
+    pub fn definitions(&self, allowed_tools: Option<&BTreeSet<String>>) -> Vec<ToolDefinition> {
+        self.entries
+            .iter()
+            .filter(|entry| {
+                allowed_tools.is_none_or(|allowed| allowed.contains(entry.definition.name.as_str()))
+            })
+            .map(|entry| entry.definition.clone())
+            .collect()
+    }
+
+    #[must_use]
+    pub fn permission_specs(
+        &self,
+        allowed_tools: Option<&BTreeSet<String>>,
+    ) -> Vec<(String, PermissionMode)> {
+        self.entries
+            .iter()
+            .filter(|entry| {
+                allowed_tools.is_none_or(|allowed| allowed.contains(entry.definition.name.as_str()))
+            })
+            .map(|entry| (entry.definition.name.clone(), entry.required_permission))
+            .collect()
+    }
+
+    pub fn normalize_allowed_tools(
+        &self,
+        values: &[String],
+    ) -> Result<Option<BTreeSet<String>>, String> {
+        if values.is_empty() {
+            return Ok(None);
+        }
+
+        let canonical_names = self
+            .entries
+            .iter()
+            .map(|entry| entry.definition.name.clone())
+            .collect::<Vec<_>>();
+        let mut name_map = canonical_names
+            .iter()
+            .map(|name| (normalize_registry_tool_name(name), name.clone()))
+            .collect::<BTreeMap<_, _>>();
+
+        for (alias, canonical) in [
+            ("read", "read_file"),
+            ("write", "write_file"),
+            ("edit", "edit_file"),
+            ("glob", "glob_search"),
+            ("grep", "grep_search"),
+        ] {
+            if canonical_names.iter().any(|name| name == canonical) {
+                name_map.insert(alias.to_string(), canonical.to_string());
+            }
+        }
+
+        let mut allowed = BTreeSet::new();
+        for value in values {
+            for token in value
+                .split(|ch: char| ch == ',' || ch.is_whitespace())
+                .filter(|token| !token.is_empty())
+            {
+                let normalized = normalize_registry_tool_name(token);
+                let canonical = name_map.get(&normalized).ok_or_else(|| {
+                    format!(
+                        "unsupported tool in --allowedTools: {token} (expected one of: {})",
+                        canonical_names.join(", ")
+                    )
+                })?;
+                allowed.insert(canonical.clone());
+            }
+        }
+
+        Ok(Some(allowed))
+    }
+
+    pub fn execute(&self, name: &str, input: &Value) -> Result<String, String> {
+        let entry = self
+            .find_entry(name)
+            .ok_or_else(|| format!("unsupported tool: {name}"))?;
+        match &entry.handler {
+            RegisteredToolHandler::Builtin => execute_tool(&entry.definition.name, input),
+            RegisteredToolHandler::Plugin(tool) => {
+                tool.execute(input).map_err(|error| error.to_string())
+            }
+        }
+    }
+}
+
+impl Default for GlobalToolRegistry {
+    fn default() -> Self {
+        Self::builtin()
+    }
+}
+
+fn normalize_registry_tool_name(value: &str) -> String {
+    let trimmed = value.trim();
+    let chars = trimmed.chars().collect::<Vec<_>>();
+    let mut normalized = String::new();
+
+    for (index, ch) in chars.iter().copied().enumerate() {
+        if matches!(ch, '-' | ' ' | '\t' | '\n') {
+            if !normalized.ends_with('_') {
+                normalized.push('_');
+            }
+            continue;
+        }
+
+        if ch == '_' {
+            if !normalized.ends_with('_') {
+                normalized.push('_');
+            }
+            continue;
+        }
+
+        if ch.is_uppercase() {
+            let prev = chars.get(index.wrapping_sub(1)).copied();
+            let next = chars.get(index + 1).copied();
+            let needs_separator = index > 0
+                && !normalized.ends_with('_')
+                && (prev.is_some_and(|prev| prev.is_lowercase() || prev.is_ascii_digit())
+                    || (prev.is_some_and(char::is_uppercase)
+                        && next.is_some_and(char::is_lowercase)));
+            if needs_separator {
+                normalized.push('_');
+            }
+            normalized.extend(ch.to_lowercase());
+            continue;
+        }
+
+        normalized.push(ch.to_ascii_lowercase());
+    }
+
+    normalized.trim_matches('_').to_string()
+}
+
+fn permission_mode_from_plugin_tool(value: &str) -> Result<PermissionMode, String> {
+    match value {
+        "read-only" => Ok(PermissionMode::ReadOnly),
+        "workspace-write" => Ok(PermissionMode::WorkspaceWrite),
+        "danger-full-access" => Ok(PermissionMode::DangerFullAccess),
+        other => Err(format!(
+            "unsupported plugin tool permission `{other}` (expected read-only, workspace-write, or danger-full-access)"
+        )),
+    }
+}
+
 #[must_use]
 #[allow(clippy::too_many_lines)]
 pub fn mvp_tool_specs() -> Vec<ToolSpec> {
@@ -1466,13 +1700,15 @@ fn build_agent_runtime(
         .clone()
         .unwrap_or_else(|| DEFAULT_AGENT_MODEL.to_string());
     let allowed_tools = job.allowed_tools.clone();
-    let api_client = AnthropicRuntimeClient::new(model, allowed_tools.clone())?;
-    let tool_executor = SubagentToolExecutor::new(allowed_tools);
+    let tool_registry = current_tool_registry()?;
+    let api_client =
+        AnthropicRuntimeClient::new(model, allowed_tools.clone(), tool_registry.clone())?;
+    let tool_executor = SubagentToolExecutor::new(allowed_tools, tool_registry.clone());
     Ok(ConversationRuntime::new(
         Session::new(),
         api_client,
         tool_executor,
-        agent_permission_policy(),
+        agent_permission_policy(&tool_registry),
         job.system_prompt.clone(),
     ))
 }
@@ -1581,10 +1817,12 @@ fn allowed_tools_for_subagent(subagent_type: &str) -> BTreeSet<String> {
     tools.into_iter().map(str::to_string).collect()
 }
 
-fn agent_permission_policy() -> PermissionPolicy {
-    mvp_tool_specs().into_iter().fold(
+fn agent_permission_policy(tool_registry: &GlobalToolRegistry) -> PermissionPolicy {
+    tool_registry.permission_specs(None).into_iter().fold(
         PermissionPolicy::new(PermissionMode::DangerFullAccess),
-        |policy, spec| policy.with_tool_requirement(spec.name, spec.required_permission),
+        |policy, (name, required_permission)| {
+            policy.with_tool_requirement(name, required_permission)
+        },
     )
 }
 
@@ -1640,10 +1878,15 @@ struct AnthropicRuntimeClient {
     client: AnthropicClient,
     model: String,
     allowed_tools: BTreeSet<String>,
+    tool_registry: GlobalToolRegistry,
 }
 
 impl AnthropicRuntimeClient {
-    fn new(model: String, allowed_tools: BTreeSet<String>) -> Result<Self, String> {
+    fn new(
+        model: String,
+        allowed_tools: BTreeSet<String>,
+        tool_registry: GlobalToolRegistry,
+    ) -> Result<Self, String> {
         let client = AnthropicClient::from_env()
             .map_err(|error| error.to_string())?
             .with_base_url(read_base_url());
@@ -1652,20 +1895,14 @@ impl AnthropicRuntimeClient {
             client,
             model,
             allowed_tools,
+            tool_registry,
         })
     }
 }
 
 impl ApiClient for AnthropicRuntimeClient {
     fn stream(&mut self, request: ApiRequest) -> Result<Vec<AssistantEvent>, RuntimeError> {
-        let tools = tool_specs_for_allowed_tools(Some(&self.allowed_tools))
-            .into_iter()
-            .map(|spec| ToolDefinition {
-                name: spec.name.to_string(),
-                description: Some(spec.description.to_string()),
-                input_schema: spec.input_schema,
-            })
-            .collect::<Vec<_>>();
+        let tools = self.tool_registry.definitions(Some(&self.allowed_tools));
         let message_request = MessageRequest {
             model: self.model.clone(),
             max_tokens: 32_000,
@@ -1716,6 +1953,8 @@ impl ApiClient for AnthropicRuntimeClient {
                                 input.push_str(&partial_json);
                             }
                         }
+                        ContentBlockDelta::ThinkingDelta { .. }
+                        | ContentBlockDelta::SignatureDelta { .. } => {}
                     },
                     ApiStreamEvent::ContentBlockStop(_) => {
                         if let Some((id, name, input)) = pending_tool.take() {
@@ -1768,32 +2007,82 @@ impl ApiClient for AnthropicRuntimeClient {
 
 struct SubagentToolExecutor {
     allowed_tools: BTreeSet<String>,
+    tool_registry: GlobalToolRegistry,
 }
 
 impl SubagentToolExecutor {
-    fn new(allowed_tools: BTreeSet<String>) -> Self {
-        Self { allowed_tools }
+    fn new(allowed_tools: BTreeSet<String>, tool_registry: GlobalToolRegistry) -> Self {
+        Self {
+            allowed_tools,
+            tool_registry,
+        }
     }
 }
 
 impl ToolExecutor for SubagentToolExecutor {
     fn execute(&mut self, tool_name: &str, input: &str) -> Result<String, ToolError> {
-        if !self.allowed_tools.contains(tool_name) {
+        let entry = self
+            .tool_registry
+            .find_entry(tool_name)
+            .ok_or_else(|| ToolError::new(format!("unsupported tool: {tool_name}")))?;
+        if !self.allowed_tools.contains(entry.definition.name.as_str()) {
             return Err(ToolError::new(format!(
                 "tool `{tool_name}` is not enabled for this sub-agent"
             )));
         }
         let value = serde_json::from_str(input)
             .map_err(|error| ToolError::new(format!("invalid tool input JSON: {error}")))?;
-        execute_tool(tool_name, &value).map_err(ToolError::new)
+        self.tool_registry
+            .execute(tool_name, &value)
+            .map_err(ToolError::new)
     }
 }
 
-fn tool_specs_for_allowed_tools(allowed_tools: Option<&BTreeSet<String>>) -> Vec<ToolSpec> {
-    mvp_tool_specs()
-        .into_iter()
-        .filter(|spec| allowed_tools.is_none_or(|allowed| allowed.contains(spec.name)))
-        .collect()
+fn current_tool_registry() -> Result<GlobalToolRegistry, String> {
+    let cwd = std::env::current_dir().map_err(|error| error.to_string())?;
+    let loader = ConfigLoader::default_for(&cwd);
+    let runtime_config = loader.load().map_err(|error| error.to_string())?;
+    let plugin_manager = build_plugin_manager(&cwd, &loader, &runtime_config);
+    let plugin_tools = plugin_manager
+        .aggregated_tools()
+        .map_err(|error| error.to_string())?;
+    GlobalToolRegistry::with_plugin_tools(plugin_tools)
+}
+
+fn build_plugin_manager(
+    cwd: &Path,
+    loader: &ConfigLoader,
+    runtime_config: &RuntimeConfig,
+) -> PluginManager {
+    let plugin_settings = runtime_config.plugins();
+    let mut plugin_config = PluginManagerConfig::new(loader.config_home().to_path_buf());
+    plugin_config.enabled_plugins = plugin_settings.enabled_plugins().clone();
+    plugin_config.external_dirs = plugin_settings
+        .external_directories()
+        .iter()
+        .map(|path| resolve_plugin_path(cwd, loader.config_home(), path))
+        .collect();
+    plugin_config.install_root = plugin_settings
+        .install_root()
+        .map(|path| resolve_plugin_path(cwd, loader.config_home(), path));
+    plugin_config.registry_path = plugin_settings
+        .registry_path()
+        .map(|path| resolve_plugin_path(cwd, loader.config_home(), path));
+    plugin_config.bundled_root = plugin_settings
+        .bundled_root()
+        .map(|path| resolve_plugin_path(cwd, loader.config_home(), path));
+    PluginManager::new(plugin_config)
+}
+
+fn resolve_plugin_path(cwd: &Path, config_home: &Path, value: &str) -> PathBuf {
+    let path = PathBuf::from(value);
+    if path.is_absolute() {
+        path
+    } else if value.starts_with('.') {
+        cwd.join(path)
+    } else {
+        config_home.join(path)
+    }
 }
 
 fn convert_messages(messages: &[ConversationMessage]) -> Vec<InputMessage> {
@@ -1860,6 +2149,7 @@ fn push_output_block(
             };
             *pending_tool = Some((id, name, initial_input));
         }
+        OutputContentBlock::Thinking { .. } | OutputContentBlock::RedactedThinking { .. } => {}
     }
 }
 
@@ -2905,9 +3195,13 @@ mod tests {
     use super::{
         agent_permission_policy, allowed_tools_for_subagent, execute_agent_with_spawn,
         execute_tool, final_assistant_text, mvp_tool_specs, persist_agent_terminal_state,
-        AgentInput, AgentJob, SubagentToolExecutor,
+        response_to_events, AgentInput, AgentJob, GlobalToolRegistry, SubagentToolExecutor,
+    };
+    use api::{MessageResponse, OutputContentBlock, Usage};
+    use plugins::{PluginTool, PluginToolDefinition, PluginToolPermission};
+    use runtime::{
+        ApiRequest, AssistantEvent, ConversationRuntime, RuntimeError, Session, ToolExecutor,
     };
-    use runtime::{ApiRequest, AssistantEvent, ConversationRuntime, RuntimeError, Session};
     use serde_json::json;
 
     fn env_lock() -> &'static Mutex<()> {
@@ -2923,6 +3217,17 @@ mod tests {
         std::env::temp_dir().join(format!("clawd-tools-{unique}-{name}"))
     }
 
+    fn make_executable(path: &PathBuf) {
+        #[cfg(unix)]
+        {
+            use std::os::unix::fs::PermissionsExt;
+
+            let mut permissions = std::fs::metadata(path).expect("metadata").permissions();
+            permissions.set_mode(0o755);
+            std::fs::set_permissions(path, permissions).expect("chmod");
+        }
+    }
+
     #[test]
     fn exposes_mvp_tools() {
         let names = mvp_tool_specs()
@@ -2952,6 +3257,170 @@ mod tests {
         assert!(error.contains("unsupported tool"));
     }
 
+    #[test]
+    fn global_registry_registers_and_executes_plugin_tools() {
+        let script = temp_path("plugin-tool.sh");
+        std::fs::write(
+            &script,
+            "#!/bin/sh\nINPUT=$(cat)\nprintf '{\"plugin\":\"%s\",\"tool\":\"%s\",\"input\":%s}\\n' \"$CLAWD_PLUGIN_ID\" \"$CLAWD_TOOL_NAME\" \"$INPUT\"\n",
+        )
+        .expect("write script");
+        make_executable(&script);
+
+        let registry = GlobalToolRegistry::with_plugin_tools(vec![PluginTool::new(
+            "demo@external",
+            "demo",
+            PluginToolDefinition {
+                name: "plugin_echo".to_string(),
+                description: Some("Echo plugin input".to_string()),
+                input_schema: json!({
+                    "type": "object",
+                    "properties": { "message": { "type": "string" } },
+                    "required": ["message"],
+                    "additionalProperties": false
+                }),
+            },
+            "sh".to_string(),
+            vec![script.display().to_string()],
+            PluginToolPermission::WorkspaceWrite,
+            script.parent().map(PathBuf::from),
+        )])
+        .expect("registry should build");
+
+        let names = registry
+            .definitions(None)
+            .into_iter()
+            .map(|definition| definition.name)
+            .collect::<Vec<_>>();
+        assert!(names.contains(&"bash".to_string()));
+        assert!(names.contains(&"plugin_echo".to_string()));
+
+        let output = registry
+            .execute("plugin_echo", &json!({ "message": "hello" }))
+            .expect("plugin tool should execute");
+        let payload: serde_json::Value = serde_json::from_str(&output).expect("valid json");
+        assert_eq!(payload["plugin"], "demo@external");
+        assert_eq!(payload["tool"], "plugin_echo");
+        assert_eq!(payload["input"]["message"], "hello");
+
+        let _ = std::fs::remove_file(script);
+    }
+
+    #[test]
+    fn global_registry_normalizes_plugin_tool_names_for_allowlists_and_execution() {
+        let script = temp_path("plugin-tool-normalized.sh");
+        std::fs::write(
+            &script,
+            "#!/bin/sh\nINPUT=$(cat)\nprintf '{\"tool\":\"%s\",\"input\":%s}\\n' \"$CLAWD_TOOL_NAME\" \"$INPUT\"\n",
+        )
+        .expect("write script");
+        make_executable(&script);
+
+        let registry = GlobalToolRegistry::with_plugin_tools(vec![PluginTool::new(
+            "demo@external",
+            "demo",
+            PluginToolDefinition {
+                name: "plugin_echo".to_string(),
+                description: Some("Echo plugin input".to_string()),
+                input_schema: json!({
+                    "type": "object",
+                    "properties": { "message": { "type": "string" } },
+                    "required": ["message"],
+                    "additionalProperties": false
+                }),
+            },
+            script.display().to_string(),
+            Vec::new(),
+            PluginToolPermission::WorkspaceWrite,
+            script.parent().map(PathBuf::from),
+        )])
+        .expect("registry should build");
+
+        let allowed = registry
+            .normalize_allowed_tools(&[String::from("PLUGIN-ECHO")])
+            .expect("plugin tool allowlist should normalize")
+            .expect("allowlist should be present");
+        assert!(allowed.contains("plugin_echo"));
+
+        let output = registry
+            .execute("plugin-echo", &json!({ "message": "hello" }))
+            .expect("normalized plugin tool name should execute");
+        let payload: serde_json::Value = serde_json::from_str(&output).expect("valid json");
+        assert_eq!(payload["tool"], "plugin_echo");
+        assert_eq!(payload["input"]["message"], "hello");
+
+        let builtin_output = GlobalToolRegistry::builtin()
+            .execute("structured-output", &json!({ "ok": true }))
+            .expect("normalized builtin tool name should execute");
+        let builtin_payload: serde_json::Value =
+            serde_json::from_str(&builtin_output).expect("valid json");
+        assert_eq!(builtin_payload["structured_output"]["ok"], true);
+
+        let _ = std::fs::remove_file(script);
+    }
+
+    #[test]
+    fn subagent_executor_executes_allowed_plugin_tools() {
+        let script = temp_path("subagent-plugin-tool.sh");
+        std::fs::write(
+            &script,
+            "#!/bin/sh\nINPUT=$(cat)\nprintf '{\"tool\":\"%s\",\"input\":%s}\\n' \"$CLAWD_TOOL_NAME\" \"$INPUT\"\n",
+        )
+        .expect("write script");
+        make_executable(&script);
+
+        let registry = GlobalToolRegistry::with_plugin_tools(vec![PluginTool::new(
+            "demo@external",
+            "demo",
+            PluginToolDefinition {
+                name: "plugin_echo".to_string(),
+                description: Some("Echo plugin input".to_string()),
+                input_schema: json!({
+                    "type": "object",
+                    "properties": { "message": { "type": "string" } },
+                    "required": ["message"],
+                    "additionalProperties": false
+                }),
+            },
+            script.display().to_string(),
+            Vec::new(),
+            PluginToolPermission::WorkspaceWrite,
+            script.parent().map(PathBuf::from),
+        )])
+        .expect("registry should build");
+
+        let mut executor =
+            SubagentToolExecutor::new(BTreeSet::from([String::from("plugin_echo")]), registry);
+        let output = executor
+            .execute("plugin-echo", r#"{"message":"hello"}"#)
+            .expect("plugin tool should execute for subagent");
+        let payload: serde_json::Value = serde_json::from_str(&output).expect("valid json");
+        assert_eq!(payload["tool"], "plugin_echo");
+        assert_eq!(payload["input"]["message"], "hello");
+
+        let _ = std::fs::remove_file(script);
+    }
+
+    #[test]
+    fn global_registry_rejects_conflicting_plugin_tool_names() {
+        let error = GlobalToolRegistry::with_plugin_tools(vec![PluginTool::new(
+            "demo@external",
+            "demo",
+            PluginToolDefinition {
+                name: "read-file".to_string(),
+                description: Some("Conflicts with builtin".to_string()),
+                input_schema: json!({ "type": "object" }),
+            },
+            "echo".to_string(),
+            Vec::new(),
+            PluginToolPermission::ReadOnly,
+            None,
+        )])
+        .expect_err("conflicting plugin tool should fail");
+
+        assert!(error.contains("conflicts with already-registered tool `read_file`"));
+    }
+
     #[test]
     fn web_fetch_returns_prompt_aware_summary() {
         let server = TestServer::spawn(Arc::new(|request_line: &str| {
@@ -3531,8 +4000,11 @@ mod tests {
                 calls: 0,
                 input_path: path.display().to_string(),
             },
-            SubagentToolExecutor::new(BTreeSet::from([String::from("read_file")])),
-            agent_permission_policy(),
+            SubagentToolExecutor::new(
+                BTreeSet::from([String::from("read_file")]),
+                GlobalToolRegistry::builtin(),
+            ),
+            agent_permission_policy(&GlobalToolRegistry::builtin()),
             vec![String::from("system prompt")],
         );
 
@@ -3558,6 +4030,42 @@ mod tests {
         let _ = std::fs::remove_file(path);
     }
 
+    #[test]
+    fn response_to_events_ignores_thinking_blocks() {
+        let events = response_to_events(MessageResponse {
+            id: "msg-1".to_string(),
+            kind: "message".to_string(),
+            model: "claude-opus-4-6".to_string(),
+            role: "assistant".to_string(),
+            content: vec![
+                OutputContentBlock::Thinking {
+                    thinking: "step 1".to_string(),
+                    signature: Some("sig_123".to_string()),
+                },
+                OutputContentBlock::Text {
+                    text: "Final answer".to_string(),
+                },
+            ],
+            stop_reason: Some("end_turn".to_string()),
+            stop_sequence: None,
+            usage: Usage {
+                input_tokens: 1,
+                output_tokens: 1,
+                cache_creation_input_tokens: 0,
+                cache_read_input_tokens: 0,
+            },
+            request_id: None,
+        });
+
+        assert!(matches!(
+            &events[0],
+            AssistantEvent::TextDelta(text) if text == "Final answer"
+        ));
+        assert!(!events
+            .iter()
+            .any(|event| matches!(event, AssistantEvent::ToolUse { .. })));
+    }
+
     #[test]
     fn agent_rejects_blank_required_fields() {
         let missing_description = execute_tool(